Starting the mod fails with:
[18:03:41] [Client thread/ERROR] [FML]: Exception loading model for variant bassebombecraft:randombookblock#normal for blockstate "bassebombecraft:randombookblock"
net.minecraftforge.client.model.ModelLoaderRegistry$LoaderException: Exception loading model bassebombecraft:randombookblock#normal with loader VariantLoader.INSTANCE, skipping
at net.minecraftforge.client.model.ModelLoaderRegistry.getModel(ModelLoaderRegistry.java:153) ~[ModelLoaderRegistry.class:?]
at net.minecraftforge.client.model.ModelLoader.registerVariant(ModelLoader.java:241) ~[ModelLoader.class:?]
at net.minecraft.client.renderer.block.model.ModelBakery.loadBlock(ModelBakery.java:153) ~[ModelBakery.class:?]
at net.minecraftforge.client.model.ModelLoader.loadBlocks(ModelLoader.java:229) ~[ModelLoader.class:?]
at net.minecraftforge.client.model.ModelLoader.setupModelRegistry(ModelLoader.java:146) ~[ModelLoader.class:?]
at net.minecraft.client.renderer.block.model.ModelManager.onResourceManagerReload(ModelManager.java:28) [ModelManager.class:?]
at net.minecraft.client.resources.SimpleReloadableResourceManager.notifyReloadListeners(SimpleReloadableResourceManager.java:132) [SimpleReloadableResourceManager.class:?]
at net.minecraft.client.resources.SimpleReloadableResourceManager.reloadResources(SimpleReloadableResourceManager.java:113) [SimpleReloadableResourceManager.class:?]
at net.minecraft.client.Minecraft.refreshResources(Minecraft.java:798) [Minecraft.class:?]
at net.minecraftforge.fml.client.FMLClientHandler.finishMinecraftLoading(FMLClientHandler.java:347) [FMLClientHandler.class:?]
at net.minecraft.client.Minecraft.init(Minecraft.java:560) [Minecraft.class:?]
at net.minecraft.client.Minecraft.run(Minecraft.java:385) [Minecraft.class:?]
at net.minecraft.client.main.Main.main(Main.java:118) [Main.class:?]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_111]
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_111]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_111]
at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_111]
at net.minecraft.launchwrapper.Launch.launch(Launch.java:135) [launchwrapper-1.12.jar:?]
at net.minecraft.launchwrapper.Launch.main(Launch.java:28) [launchwrapper-1.12.jar:?]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_111]
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_111]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_111]
at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_111]
at net.minecraftforge.gradle.GradleStartCommon.launch(GradleStartCommon.java:97) [start/:?]
at GradleStart.main(GradleStart.java:26) [start/:?]
Caused by: net.minecraft.client.renderer.block.model.ModelBlockDefinition$MissingVariantException
at net.minecraft.client.renderer.block.model.ModelBlockDefinition.getVariant(ModelBlockDefinition.java:78) ~[ModelBlockDefinition.class:?]
at net.minecraftforge.client.model.ModelLoader$VariantLoader.loadModel(ModelLoader.java:1184) ~[ModelLoader$VariantLoader.class:?]
at net.minecraftforge.client.model.ModelLoaderRegistry.getModel(ModelLoaderRegistry.java:149) ~[ModelLoaderRegistry.class:?]
... 24 more

See #27.

All JSON/PNG file names should be lower case, see #27.