This is the crash log when trying to load performant:

Description: Exception in server tick loop

java.lang.NoClassDefFoundError: net/minecraft/world/World$Anonymous$470a8cadb93d44d08c66f00809298f15
at net.minecraft.world.World.(World.java:126)
at net.minecraft.world.WorldServer.(WorldServer.java:110)
at org.spongepowered.common.world.WorldManager.createWorldFromProperties(WorldManager.java:873)
at org.spongepowered.common.world.WorldManager.loadAllWorlds(WorldManager.java:840)
at net.minecraft.server.MinecraftServer.func_71247_a(MinecraftServer.java:4390)
at net.minecraft.server.dedicated.DedicatedServer.func_71197_b(DedicatedServer.java:270)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:486)
at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.ClassNotFoundException: net.minecraft.world.World$Anonymous$470a8cadb93d44d08c66f00809298f15
at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:191)
at java.lang.ClassLoader.loadClass(ClassLoader.java:418)
at java.lang.ClassLoader.loadClass(ClassLoader.java:351)
... 8 more
Caused by: net.minecraftforge.fml.common.asm.ASMTransformerWrapper$TransformerException: Exception in class transformer git.jbredwards.fluidlogged_api.asm.swapper.ASMSwapper@3c232051 from coremod Fluidlogged Plugin
at net.minecraftforge.fml.common.asm.ASMTransformerWrapper$TransformerWrapper.transform(ASMTransformerWrapper.java:260)
at net.minecraft.launchwrapper.LaunchClassLoader.runTransformers(LaunchClassLoader.java:279)
at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:176)
... 10 more
Caused by: java.lang.NullPointerException

LTM if there's any info I should provide or if it's already clear

Sorry for the late reply, please give me some time as i cannot do tests on the server right now

closed due to inactivity, but the class seeming to cause the crash has been removed, so probably fixed

can you send the full log?