Bukkit

19:07:16 [WARNING] Wrong location for EntityExperienceOrb['Experience Orb'/17812, l='HungerGames', x=-135.00, y=54.10, z=-80.00] in world 'HungerGames'!
19:07:16 [WARNING] Entity is at -135.0,-80.0 (chunk -9,-5) but was stored in chunk -9,-6
19:07:16 [WARNING] [Multiverse-Core] Task #12155 for Multiverse-Core v2.5-b654 generated an exception
java.lang.IllegalStateException: Lost reference to bukkit world 'HungerGames'
        at com.onarandombox.MultiverseCore.MVWorld.getCBWorld(MVWorld.java:488)
        at com.onarandombox.MultiverseCore.listeners.MVPlayerListener$2.run(MVPlayerListener.java:345)
        at org.bukkit.craftbukkit.v1_4_6.scheduler.CraftTask.run(CraftTask.java:53)
        at org.bukkit.craftbukkit.v1_4_6.scheduler.CraftScheduler.mainThreadHeartbeat(CraftScheduler.java:345)
        at net.minecraft.server.v1_4_6.MinecraftServer.r(MinecraftServer.java:530)
        at net.minecraft.server.v1_4_6.DedicatedServer.r(DedicatedServer.java:224)
        at net.minecraft.server.v1_4_6.MinecraftServer.q(MinecraftServer.java:494)
        at net.minecraft.server.v1_4_6.MinecraftServer.run(MinecraftServer.java:427)
        at net.minecraft.server.v1_4_6.ThreadServerApplication.run(SourceFile:849)

19:07:26 [WARNING] [Hunger Games Map Generator Server] No lever

So many problems with this plugin. :(

I'm not sure what the problem is here, but it looks like you are trying to regenerate while Multiverse is managing your worlds, and the world needs to be unloaded completely before regeneration.