I only have this mod installed on the newest forge, and every time i create a new world. this:
---- Minecraft Crash Report ----
// Sorry :(

Time: 12/6/14 11:38 AM
Description: Exception getting block type in world

java.lang.RuntimeException: Caught exception while constructing template blocks: Vanilla Block Rule id: minecraft:sticky_piston meta: 11 buildPass: 0
at net.shadowmage.ancientwarfare.structure.template.build.StructureBuilder.instantConstruction(StructureBuilder.java:109)
at net.shadowmage.ancientwarfare.structure.template.build.StructureBuilderWorldGen.instantConstruction(StructureBuilderWorldGen.java:140)
at net.shadowmage.ancientwarfare.structure.world_gen.WorldStructureGenerator.generateStructureAt(WorldStructureGenerator.java:202)
at net.shadowmage.ancientwarfare.structure.world_gen.WorldStructureGenerator.attemptStructureGenerationAt(WorldStructureGenerator.java:193)
at net.shadowmage.ancientwarfare.structure.world_gen.WorldStructureGenerator.generateAt(WorldStructureGenerator.java:127)
at net.shadowmage.ancientwarfare.structure.world_gen.WorldStructureGenerator.generate(WorldStructureGenerator.java:97)
at cpw.mods.fml.common.registry.GameRegistry.generateWorld(GameRegistry.java:106)
at net.minecraft.world.gen.ChunkProviderServer.func_73153_a(ChunkProviderServer.java:280)
at net.minecraft.world.chunk.Chunk.func_76624_a(Chunk.java:1055)
at net.minecraft.world.gen.ChunkProviderServer.originalLoadChunk(ChunkProviderServer.java:190)
at net.minecraft.world.gen.ChunkProviderServer.loadChunk(ChunkProviderServer.java:131)
at net.minecraft.world.gen.ChunkProviderServer.func_73158_c(ChunkProviderServer.java:101)
at net.minecraft.world.gen.ChunkProviderServer.func_73154_d(ChunkProviderServer.java:199)
at net.minecraft.world.World.func_72964_e(World.java:419)
at net.minecraft.world.World.func_147439_a(World.java:345)
at net.minecraft.world.World.func_147437_c(World.java:365)
at net.minecraft.world.World.func_147474_b(World.java:329)
at net.minecraft.world.WorldProvider.func_76566_a(WorldProvider.java:71)
at net.minecraft.world.WorldServer.func_73052_b(WorldServer.java:748)
at net.minecraft.world.WorldServer.func_72963_a(WorldServer.java:715)
at net.minecraft.world.World.(World.java:260)
at net.minecraft.world.WorldServer.(WorldServer.java:97)
at net.minecraft.server.integrated.IntegratedServer.func_71247_a(IntegratedServer.java:62)
at net.minecraft.server.integrated.IntegratedServer.func_71197_b(IntegratedServer.java:92)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:387)
at net.minecraft.server.MinecraftServer$2.run(MinecraftServer.java:685)
Caused by: java.lang.NullPointerException
at net.minecraft.world.WorldServer.func_147452_c(WorldServer.java:925)
at net.minecraft.block.BlockPistonBase.func_150078_e(BlockPistonBase.java:139)
at net.minecraft.block.BlockPistonBase.func_149726_b(BlockPistonBase.java:116)
at net.minecraft.world.chunk.Chunk.func_150807_a(Chunk.java:655)
at net.minecraft.world.World.func_147465_d(World.java:451)
at net.shadowmage.ancientwarfare.structure.template.build.StructureBuilder.placeBlock(StructureBuilder.java:153)
at net.shadowmage.ancientwarfare.structure.template.build.StructureBuilderWorldGen.placeBlock(StructureBuilderWorldGen.java:72)
at net.shadowmage.ancientwarfare.structure.template.plugin.default_plugins.block_rules.TemplateRuleVanillaBlocks.handlePlacement(TemplateRuleVanillaBlocks.java:70)
at net.shadowmage.ancientwarfare.structure.template.build.StructureBuilder.placeRule(StructureBuilder.java:215)
at net.shadowmage.ancientwarfare.structure.template.build.StructureBuilder.placeCurrentPosition(StructureBuilder.java:184)
at net.shadowmage.ancientwarfare.structure.template.build.StructureBuilder.instantConstruction(StructureBuilder.java:103)
... 25 more

A detailed walkthrough of the error, its code path and all known details is as follows:

-- Head --
Stacktrace:
at net.shadowmage.ancientwarfare.structure.template.build.StructureBuilder.instantConstruction(StructureBuilder.java:109)
at net.shadowmage.ancientwarfare.structure.template.build.StructureBuilderWorldGen.instantConstruction(StructureBuilderWorldGen.java:140)
at net.shadowmage.ancientwarfare.structure.world_gen.WorldStructureGenerator.generateStructureAt(WorldStructureGenerator.java:202)
at net.shadowmage.ancientwarfare.structure.world_gen.WorldStructureGenerator.attemptStructureGenerationAt(WorldStructureGenerator.java:193)
at net.shadowmage.ancientwarfare.structure.world_gen.WorldStructureGenerator.generateAt(WorldStructureGenerator.java:127)
at net.shadowmage.ancientwarfare.structure.world_gen.WorldStructureGenerator.generate(WorldStructureGenerator.java:97)
at cpw.mods.fml.common.registry.GameRegistry.generateWorld(GameRegistry.java:106)
at net.minecraft.world.gen.ChunkProviderServer.func_73153_a(ChunkProviderServer.java:280)
at net.minecraft.world.chunk.Chunk.func_76624_a(Chunk.java:1055)
at net.minecraft.world.gen.ChunkProviderServer.originalLoadChunk(ChunkProviderServer.java:190)
at net.minecraft.world.gen.ChunkProviderServer.loadChunk(ChunkProviderServer.java:131)
at net.minecraft.world.gen.ChunkProviderServer.func_73158_c(ChunkProviderServer.java:101)
at net.minecraft.world.gen.ChunkProviderServer.func_73154_d(ChunkProviderServer.java:199)
at net.minecraft.world.World.func_72964_e(World.java:419)

-- Requested block coordinates --
Details:
Found chunk: true
Location: World: (-26,64,210), Chunk: (at 6,4,2 in -2,13; contains blocks -32,0,208 to -17,255,223), Region: (-1,0; contains chunks -32,0 to -1,31, blocks -512,0,0 to -1,255,511)
Stacktrace:
at net.minecraft.world.World.func_147439_a(World.java:345)
at net.minecraft.world.World.func_147437_c(World.java:365)
at net.minecraft.world.World.func_147474_b(World.java:329)
at net.minecraft.world.WorldProvider.func_76566_a(WorldProvider.java:71)
at net.minecraft.world.WorldServer.func_73052_b(WorldServer.java:748)
at net.minecraft.world.WorldServer.func_72963_a(WorldServer.java:715)

-- Affected level --
Details:
Level name: New Worl
All players: 0 total; []
Chunk stats: ServerChunkCache: 314 Drop: 0
Level seed: 2832111046784483180
Level generator: ID 01 - flat, ver 0. Features enabled: true
Level generator options:
Level spawn location: World: (0,0,0), Chunk: (at 0,0,0 in 0,0; contains blocks 0,0,0 to 15,255,15), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)
Level time: 0 game time, 0 day time
Level dimension: 0
Level storage version: 0x04ABD - Anvil
Level weather: Rain time: 0 (now: false), thunder time: 0 (now: false)
Level game mode: Game mode: creative (ID 1). Hardcore: false. Cheats: true
Stacktrace:
at net.minecraft.world.World.(World.java:260)
at net.minecraft.world.WorldServer.(WorldServer.java:97)
at net.minecraft.server.integrated.IntegratedServer.func_71247_a(IntegratedServer.java:62)
at net.minecraft.server.integrated.IntegratedServer.func_71197_b(IntegratedServer.java:92)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:387)
at net.minecraft.server.MinecraftServer$2.run(MinecraftServer.java:685)

-- System Details --
Details:
Minecraft Version: 1.7.10
Operating System: Windows 7 (amd64) version 6.1
Java Version: 1.7.0_65, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 1812825312 bytes (1728 MB) / 2098655232 bytes (2001 MB) up to 3006529536 bytes (2867 MB)
JVM Flags: 6 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx3G -XX:+UseConcMarkSweepGC -XX:+CMSIncrementalMode -XX:-UseAdaptiveSizePolicy -Xmn2G
AABB Pool Size: 0 (0 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
FML: MCP v9.05 FML v7.10.85.1240 Minecraft Forge 10.13.2.1240 9 mods loaded, 9 mods active
mcp{9.05} Minecraft Coder Pack Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
FML{7.10.85.1240} Forge Mod Loader Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
Forge{10.13.2.1240} Minecraft Forge Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
AncientWarfare{2.3.77-beta-MC1.7.10} Ancient Warfare Core Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
AncientWarfareAutomation{2.3.77-beta-MC1.7.10} Ancient Warfare Automation Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
AncientWarfareNEIPlugin{2.3.77-beta-MC1.7.10} Ancient Warfare NEI Plugin Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
AncientWarfareNpc{2.3.77-beta-MC1.7.10} Ancient Warfare NPCs Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
AncientWarfareStructure{2.3.77-beta-MC1.7.10} Ancient Warfare Structures Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
AncientWarfareVehicle{2.3.77-beta-MC1.7.10} Ancient Warfare Vehicles Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
Profiler Position: N/A (disabled)
Player Count: 0 / 8; []
Type: Integrated Server (map_client.txt)
Is Modded: Definitely; Client brand changed to 'fml,forge'

"Level generator: ID 01 - flat"

This is a known issue with structures containing pistons generating in a flat world. See #150 for more info.

Thank you

Ah thank you, i use flat worlds when testing mods.

Duplicate of #150