When I try to run "gradle build" the build fails because it can't fetch lwjgl from libraries.minecraft.net.
I can download it manually just fine, but don't know where to put it to make the script work.
This is trying to build the 1.10.2 branch.

This mapping 'snapshot_20160518' was designed for MC 1.9.4! Use at your own peril.
#################################################
ForgeGradle 2.2-SNAPSHOT-59eb824
https://github.com/MinecraftForge/ForgeGradle
#################################################
Powered by MCP unknown
http://modcoderpack.com
by: Searge, ProfMobius, Fesh0r,
R4wk, ZeuX, IngisKahn, bspkrs
#################################################
:extractMcpMappings SKIPPED
:deobfCompileDeobfDepTask0 SKIPPED
:deobfCompileDeobfDepTask1 SKIPPED
:deobfCompileDeobfDepTask2 SKIPPED
:deobfCompileRemapDepSourcesTask3 SKIPPED
:deobfCompileRemapDepSourcesTask4 SKIPPED
:deobfCompileRemapDepSourcesTask5 SKIPPED
:deobfCompileDummyTask
:getVersionJson
:extractUserdev UP-TO-DATE
:downloadClient SKIPPED
:downloadServer SKIPPED
:splitServerJar SKIPPED
:mergeJars SKIPPED
:applyBinaryPatches SKIPPED
:deobfProvidedDummyTask
:extractDependencyATs SKIPPED
:extractMcpData SKIPPED
:genSrgs SKIPPED
:deobfMcMCP SKIPPED
:sourceApiJava UP-TO-DATE
:compileApiJava UP-TO-DATE
:processApiResources UP-TO-DATE
:apiClasses UP-TO-DATE
:sourceMainJava UP-TO-DATE
:compileJava
FAILURE: Build failed with an exception.

• What went wrong:
  Could not resolve all dependencies for configuration ':forgeGradleMcDeps'.

Could not download lwjgl.jar (org.lwjgl.lwjgl:lwjgl:2.9.4-nightly-20150209)
Could not get resource 'https://libraries.minecraft.net/org/lwjgl/lwjgl/lwjgl/2.9.4-nightly-20150209/lwjgl-2.9.4-nightly-20150209.jar'.
> Could not GET 'https://libraries.minecraft.net/org/lwjgl/lwjgl/lwjgl/2.9.4-nightly-20150209/lwjgl-2.9.4-nightly-20150209.jar'. Received status code 500 from server: Internal Server Error

• Try:
  Run with --info or --debug option to get more log output.

• Exception is:
  org.gradle.api.artifacts.ResolveException: Could not resolve all dependencies for configuration ':forgeGradleMcDeps'.
  at org.gradle.api.internal.artifacts.ivyservice.ErrorHandlingConfigurationResolver.wrapException(ErrorHandlingConfigurationResolver.java:70)
  at org.gradle.api.internal.artifacts.ivyservice.ErrorHandlingConfigurationResolver.access$000(ErrorHandlingConfigurationResolver.java:33)
  at org.gradle.api.internal.artifacts.ivyservice.ErrorHandlingConfigurationResolver$ErrorHandlingResolvedConfiguration.getFiles(ErrorHandlingConfigurationResolver.java:199)
  at org.gradle.api.internal.artifacts.configurations.DefaultConfiguration$ConfigurationFileCollection.getFiles(DefaultConfiguration.java:668)
  at org.gradle.api.internal.artifacts.configurations.DefaultConfiguration.getFiles(DefaultConfiguration.java:292)
  at org.gradle.api.internal.artifacts.configurations.DefaultConfiguration_Decorated.getFiles(Unknown Source)
  at org.gradle.api.internal.file.collections.DefaultFileCollectionResolveContext$FileTreeConverter.convertInto(DefaultFileCollectionResolveContext.java:202)
  at org.gradle.api.internal.file.collections.DefaultFileCollectionResolveContext.doResolve(DefaultFileCollectionResolveContext.java:103)
  at org.gradle.api.internal.file.collections.DefaultFileCollectionResolveContext.resolveAsFileTrees(DefaultFileCollectionResolveContext.java:74)
  at org.gradle.api.internal.file.collections.DefaultFileCollectionResolveContext$FileTreeConverter.convertInto(DefaultFileCollectionResolveContext.java:188)
  at org.gradle.api.internal.file.collections.DefaultFileCollectionResolveContext.doResolve(DefaultFileCollectionResolveContext.java:98)
  at org.gradle.api.internal.file.collections.DefaultFileCollectionResolveContext.resolveAsFileTrees(DefaultFileCollectionResolveContext.java:74)
  at org.gradle.api.internal.changedetection.state.DefaultFileCollectionSnapshotter.visitFiles(DefaultFileCollectionSnapshotter.java:41)
  at org.gradle.api.internal.changedetection.state.AbstractFileCollectionSnapshotter.snapshot(AbstractFileCollectionSnapshotter.java:57)
  at org.gradle.api.internal.changedetection.state.DefaultFileCollectionSnapshotter.snapshot(DefaultFileCollectionSnapshotter.java:29)
  at org.gradle.api.internal.changedetection.rules.AbstractFileSnapshotTaskStateChanges.createSnapshot(AbstractFileSnapshotTaskStateChanges.java:47)
  at org.gradle.api.internal.changedetection.rules.InputFilesTaskStateChanges.(InputFilesTaskStateChanges.java:33)
  at org.gradle.api.internal.changedetection.rules.TaskUpToDateState.(TaskUpToDateState.java:52)
  at org.gradle.api.internal.changedetection.changes.DefaultTaskArtifactStateRepository$TaskArtifactStateImpl.getStates(DefaultTaskArtifactStateRepository.java:142)
  at org.gradle.api.internal.changedetection.changes.DefaultTaskArtifactStateRepository$TaskArtifactStateImpl.isUpToDate(DefaultTaskArtifactStateRepository.java:73)
  at org.gradle.api.internal.tasks.execution.SkipUpToDateTaskExecuter.execute(SkipUpToDateTaskExecuter.java:55)
  at org.gradle.api.internal.tasks.execution.ValidatingTaskExecuter.execute(ValidatingTaskExecuter.java:58)
  at org.gradle.api.internal.tasks.execution.SkipEmptySourceFilesTaskExecuter.execute(SkipEmptySourceFilesTaskExecuter.java:52)
  at org.gradle.api.internal.tasks.execution.SkipTaskWithNoActionsExecuter.execute(SkipTaskWithNoActionsExecuter.java:52)
  at org.gradle.api.internal.tasks.execution.SkipOnlyIfTaskExecuter.execute(SkipOnlyIfTaskExecuter.java:53)
  at org.gradle.api.internal.tasks.execution.ExecuteAtMostOnceTaskExecuter.execute(ExecuteAtMostOnceTaskExecuter.java:43)
  at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker.execute(DefaultTaskGraphExecuter.java:203)
  at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker.execute(DefaultTaskGraphExecuter.java:185)
  at org.gradle.execution.taskgraph.AbstractTaskPlanExecutor$TaskExecutorWorker.processTask(AbstractTaskPlanExecutor.java:66)
  at org.gradle.execution.taskgraph.AbstractTaskPlanExecutor$TaskExecutorWorker.run(AbstractTaskPlanExecutor.java:50)
  at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor.process(DefaultTaskPlanExecutor.java:25)
  at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter.execute(DefaultTaskGraphExecuter.java:110)
  at org.gradle.execution.SelectedTaskExecutionAction.execute(SelectedTaskExecutionAction.java:37)
  at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:37)
  at org.gradle.execution.DefaultBuildExecuter.access$000(DefaultBuildExecuter.java:23)
  at org.gradle.execution.DefaultBuildExecuter$1.proceed(DefaultBuildExecuter.java:43)
  at org.gradle.execution.DryRunBuildExecutionAction.execute(DryRunBuildExecutionAction.java:32)
  at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:37)
  at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:30)
  at org.gradle.initialization.DefaultGradleLauncher$4.run(DefaultGradleLauncher.java:154)
  at org.gradle.internal.Factories$1.create(Factories.java:22)
  at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:90)
  at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:52)
  at org.gradle.initialization.DefaultGradleLauncher.doBuildStages(DefaultGradleLauncher.java:151)
  at org.gradle.initialization.DefaultGradleLauncher.access$200(DefaultGradleLauncher.java:32)
  at org.gradle.initialization.DefaultGradleLauncher$1.create(DefaultGradleLauncher.java:99)
  at org.gradle.initialization.DefaultGradleLauncher$1.create(DefaultGradleLauncher.java:93)
  at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:90)
  at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:62)
  at org.gradle.initialization.DefaultGradleLauncher.doBuild(DefaultGradleLauncher.java:93)
  at org.gradle.initialization.DefaultGradleLauncher.run(DefaultGradleLauncher.java:82)
  at org.gradle.launcher.exec.InProcessBuildActionExecuter$DefaultBuildController.run(InProcessBuildActionExecuter.java:94)
  at org.gradle.tooling.internal.provider.ExecuteBuildActionRunner.run(ExecuteBuildActionRunner.java:28)
  at org.gradle.launcher.exec.ChainingBuildActionRunner.run(ChainingBuildActionRunner.java:35)
  at org.gradle.launcher.exec.InProcessBuildActionExecuter.execute(InProcessBuildActionExecuter.java:43)
  at org.gradle.launcher.exec.InProcessBuildActionExecuter.execute(InProcessBuildActionExecuter.java:28)
  at org.gradle.launcher.exec.ContinuousBuildActionExecuter.execute(ContinuousBuildActionExecuter.java:81)
  at org.gradle.launcher.exec.ContinuousBuildActionExecuter.execute(ContinuousBuildActionExecuter.java:46)
  at org.gradle.launcher.exec.DaemonUsageSuggestingBuildActionExecuter.execute(DaemonUsageSuggestingBuildActionExecuter.java:51)
  at org.gradle.launcher.exec.DaemonUsageSuggestingBuildActionExecuter.execute(DaemonUsageSuggestingBuildActionExecuter.java:28)
  at org.gradle.launcher.cli.RunBuildAction.run(RunBuildAction.java:43)
  at org.gradle.internal.Actions$RunnableActionAdapter.execute(Actions.java:173)
  at org.gradle.launcher.cli.CommandLineActionFactory$ParseAndBuildAction.execute(CommandLineActionFactory.java:241)
  at org.gradle.launcher.cli.CommandLineActionFactory$ParseAndBuildAction.execute(CommandLineActionFactory.java:214)
  at org.gradle.launcher.cli.JavaRuntimeValidationAction.execute(JavaRuntimeValidationAction.java:35)
  at org.gradle.launcher.cli.JavaRuntimeValidationAction.execute(JavaRuntimeValidationAction.java:24)
  at org.gradle.launcher.cli.CommandLineActionFactory$WithLogging.execute(CommandLineActionFactory.java:207)
  at org.gradle.launcher.cli.CommandLineActionFactory$WithLogging.execute(CommandLineActionFactory.java:169)
  at org.gradle.launcher.cli.ExceptionReportingAction.execute(ExceptionReportingAction.java:33)
  at org.gradle.launcher.cli.ExceptionReportingAction.execute(ExceptionReportingAction.java:22)
  at org.gradle.launcher.Main.doAction(Main.java:33)
  at org.gradle.launcher.bootstrap.EntryPoint.run(EntryPoint.java:45)
  at org.gradle.launcher.bootstrap.ProcessBootstrap.runNoExit(ProcessBootstrap.java:55)
  at org.gradle.launcher.bootstrap.ProcessBootstrap.run(ProcessBootstrap.java:36)
  at org.gradle.launcher.GradleMain.main(GradleMain.java:23)
  Caused by: org.gradle.internal.resolve.ArtifactResolveException: Could not download lwjgl.jar (org.lwjgl.lwjgl:lwjgl:2.9.4-nightly-20150209)
  at org.gradle.api.internal.artifacts.repositories.resolver.ExternalResourceResolver.resolveArtifact(ExternalResourceResolver.java:240)
  at org.gradle.api.internal.artifacts.repositories.resolver.ExternalResourceResolver$RemoteRepositoryAccess.resolveArtifact(ExternalResourceResolver.java:436)
  at org.gradle.api.internal.artifacts.ivyservice.ivyresolve.CacheLockReleasingModuleComponentsRepository$LockReleasingRepositoryAccess$5.run(CacheLockReleasingModuleComponentsRepository.java:96)
  at org.gradle.internal.Factories$1.create(Factories.java:22)
  at org.gradle.cache.internal.DefaultCacheAccess.longRunningOperation(DefaultCacheAccess.java:242)
  at org.gradle.cache.internal.DefaultCacheAccess.longRunningOperation(DefaultCacheAccess.java:313)
  at org.gradle.cache.internal.DefaultPersistentDirectoryStore.longRunningOperation(DefaultPersistentDirectoryStore.java:114)
  at org.gradle.cache.internal.DefaultCacheFactory$ReferenceTrackingCache.longRunningOperation(DefaultCacheFactory.java:179)
  at org.gradle.api.internal.artifacts.ivyservice.DefaultCacheLockingManager.longRunningOperation(DefaultCacheLockingManager.java:56)
  at org.gradle.api.internal.artifacts.ivyservice.ivyresolve.CacheLockReleasingModuleComponentsRepository$LockReleasingRepositoryAccess.resolveArtifact(CacheLockReleasingModuleComponentsRepository.java:94)
  at org.gradle.api.internal.artifacts.ivyservice.ivyresolve.CachingModuleComponentRepository$ResolveAndCacheRepositoryAccess.resolveArtifact(CachingModuleComponentRepository.java:342)
  at org.gradle.api.internal.artifacts.ivyservice.ivyresolve.BaseModuleComponentRepositoryAccess.resolveArtifact(BaseModuleComponentRepositoryAccess.java:54)
  at org.gradle.api.internal.artifacts.ivyservice.ivyresolve.memcache.InMemoryCachedModuleComponentRepository$CachedAccess.resolveArtifact(InMemoryCachedModuleComponentRepository.java:82)
  at org.gradle.api.internal.artifacts.ivyservice.ivyresolve.ErrorHandlingModuleComponentRepository$ErrorHandlingModuleComponentRepositoryAccess.resolveArtifact(ErrorHandlingModuleComponentRepository.java:116)
  at org.gradle.api.internal.artifacts.ivyservice.ivyresolve.RepositoryChainArtifactResolver.resolveArtifact(RepositoryChainArtifactResolver.java:65)
  at org.gradle.api.internal.artifacts.ivyservice.resolveengine.ComponentResolversChain$ArtifactResolverChain.resolveArtifact(ComponentResolversChain.java:98)
  at org.gradle.api.internal.artifacts.ivyservice.ContextualArtifactResolver$3.execute(ContextualArtifactResolver.java:61)
  at org.gradle.api.internal.artifacts.ivyservice.ContextualArtifactResolver$3.execute(ContextualArtifactResolver.java:59)
  at org.gradle.internal.Transformers$4.transform(Transformers.java:169)
  at org.gradle.api.internal.artifacts.ivyservice.DefaultIvyContextManager.withIvy(DefaultIvyContextManager.java:61)
  at org.gradle.api.internal.artifacts.ivyservice.DefaultIvyContextManager.withIvy(DefaultIvyContextManager.java:39)
  at org.gradle.api.internal.artifacts.ivyservice.ContextualArtifactResolver$4.run(ContextualArtifactResolver.java:69)
  at org.gradle.internal.Factories$1.create(Factories.java:22)
  at org.gradle.cache.internal.DefaultCacheAccess.useCache(DefaultCacheAccess.java:192)
  at org.gradle.cache.internal.DefaultCacheAccess.useCache(DefaultCacheAccess.java:175)
  at org.gradle.cache.internal.DefaultPersistentDirectoryStore.useCache(DefaultPersistentDirectoryStore.java:106)
  at org.gradle.cache.internal.DefaultCacheFactory$ReferenceTrackingCache.useCache(DefaultCacheFactory.java:187)
  at org.gradle.api.internal.artifacts.ivyservice.DefaultCacheLockingManager.useCache(DefaultCacheLockingManager.java:64)
  at org.gradle.api.internal.artifacts.ivyservice.ContextualArtifactResolver.executeInContext(ContextualArtifactResolver.java:67)
  at org.gradle.api.internal.artifacts.ivyservice.ContextualArtifactResolver.resolveArtifact(ContextualArtifactResolver.java:59)
  at org.gradle.api.internal.artifacts.ivyservice.ivyresolve.ErrorHandlingArtifactResolver.resolveArtifact(ErrorHandlingArtifactResolver.java:53)
  at org.gradle.api.internal.artifacts.ivyservice.resolveengine.artifact.DefaultArtifactSet$LazyArtifactSource.create(DefaultArtifactSet.java:93)
  at org.gradle.api.internal.artifacts.ivyservice.resolveengine.artifact.DefaultArtifactSet$LazyArtifactSource.create(DefaultArtifactSet.java:80)
  at org.gradle.api.internal.artifacts.DefaultResolvedArtifact.getFile(DefaultResolvedArtifact.java:90)
  at org.gradle.api.internal.artifacts.ivyservice.DefaultLenientConfiguration$2.run(DefaultLenientConfiguration.java:122)
  at org.gradle.internal.Factories$1.create(Factories.java:22)
  at org.gradle.cache.internal.DefaultCacheAccess.useCache(DefaultCacheAccess.java:192)
  at org.gradle.cache.internal.DefaultCacheAccess.useCache(DefaultCacheAccess.java:175)
  at org.gradle.cache.internal.DefaultPersistentDirectoryStore.useCache(DefaultPersistentDirectoryStore.java:106)
  at org.gradle.cache.internal.DefaultCacheFactory$ReferenceTrackingCache.useCache(DefaultCacheFactory.java:187)
  at org.gradle.api.internal.artifacts.ivyservice.DefaultCacheLockingManager.useCache(DefaultCacheLockingManager.java:64)
  at org.gradle.api.internal.artifacts.ivyservice.DefaultLenientConfiguration.getFiles(DefaultLenientConfiguration.java:119)
  at org.gradle.api.internal.artifacts.ivyservice.DefaultLenientConfiguration.getFilesStrict(DefaultLenientConfiguration.java:91)
  at org.gradle.api.internal.artifacts.ivyservice.DefaultResolvedConfiguration.getFiles(DefaultResolvedConfiguration.java:45)
  at org.gradle.api.internal.artifacts.ivyservice.SelfResolvingDependencyConfigurationResolver$FilesAggregatingResolvedConfiguration.getFiles(SelfResolvingDependencyConfigurationResolver.java:87)
  at org.gradle.api.internal.artifacts.ivyservice.ErrorHandlingConfigurationResolver$ErrorHandlingResolvedConfiguration.getFiles(ErrorHandlingConfigurationResolver.java:197)
  ... 72 more
  Caused by: org.gradle.api.resources.ResourceException: Could not get resource 'https://libraries.minecraft.net/org/lwjgl/lwjgl/lwjgl/2.9.4-nightly-20150209/lwjgl-2.9.4-nightly-20150209.jar'.
  at org.gradle.internal.resource.ResourceExceptions.failure(ResourceExceptions.java:69)
  at org.gradle.internal.resource.ResourceExceptions.getFailed(ResourceExceptions.java:52)
  at org.gradle.api.internal.artifacts.repositories.resolver.DefaultExternalResourceArtifactResolver.downloadStaticResource(DefaultExternalResourceArtifactResolver.java:95)
  at org.gradle.api.internal.artifacts.repositories.resolver.DefaultExternalResourceArtifactResolver.resolveArtifact(DefaultExternalResourceArtifactResolver.java:56)
  at org.gradle.api.internal.artifacts.repositories.resolver.ExternalResourceResolver.download(ExternalResourceResolver.java:252)
  at org.gradle.api.internal.artifacts.repositories.resolver.ExternalResourceResolver.resolveArtifact(ExternalResourceResolver.java:238)
  ... 117 more
  Caused by: org.gradle.api.UncheckedIOException: Could not GET 'https://libraries.minecraft.net/org/lwjgl/lwjgl/lwjgl/2.9.4-nightly-20150209/lwjgl-2.9.4-nightly-20150209.jar'. Received status code 500 from server: Internal Server Error
  at org.gradle.internal.resource.transport.http.HttpClientHelper.processResponse(HttpClientHelper.java:112)
  at org.gradle.internal.resource.transport.http.HttpClientHelper.performGet(HttpClientHelper.java:62)
  at org.gradle.internal.resource.transport.http.HttpResourceAccessor.openResource(HttpResourceAccessor.java:51)
  at org.gradle.internal.resource.transport.http.HttpResourceAccessor.openResource(HttpResourceAccessor.java:34)
  at org.gradle.internal.resource.transfer.DefaultExternalResourceConnector.openResource(DefaultExternalResourceConnector.java:41)
  at org.gradle.internal.resource.transfer.ProgressLoggingExternalResourceAccessor.openResource(ProgressLoggingExternalResourceAccessor.java:36)
  at org.gradle.internal.resource.transport.DefaultExternalResourceRepository.getResource(DefaultExternalResourceRepository.java:63)
  at org.gradle.internal.resource.transfer.DefaultCacheAwareExternalResourceAccessor.getResource(DefaultCacheAwareExternalResourceAccessor.java:76)
  at org.gradle.api.internal.artifacts.repositories.resolver.DefaultExternalResourceArtifactResolver.downloadStaticResource(DefaultExternalResourceArtifactResolver.java:86)
  ... 120 more

BUILD FAILED

Try again in a little while. Sometimes the Minecraft file servers error out for me, too.

Closing for now, let me know if you still can't get it to work.