Dynamic Transport Crash

Description: Exception while updating neighbours

java.lang.NullPointerException
	at com.slimevoid.dynamictransport.tileentity.TileEntityFloorMarker.callElevator(TileEntityFloorMarker.java:81)
	at com.slimevoid.dynamictransport.tileentity.TileEntityFloorMarker.onBlockNeighborChange(TileEntityFloorMarker.java:72)
	at com.slimevoid.library.blocks.BlockBase.func_71863_a(BlockBase.java:416)
	at net.minecraft.world.World.func_72821_m(World.java:845)
	at net.minecraft.world.World.func_72898_h(World.java:788)
	at net.minecraft.world.World.func_72851_f(World.java:741)
	at net.minecraft.world.World.func_72921_c(World.java:664)
	at net.minecraft.block.BlockLever.func_71903_a(BlockLever.java:314)
	at net.minecraft.item.ItemInWorldManager.func_73078_a(ItemInWorldManager.java:421)
	at net.minecraft.network.NetServerHandler.func_72472_a(NetServerHandler.java:556)
	at net.minecraft.network.packet.Packet15Place.func_73279_a(SourceFile:58)
	at net.minecraft.network.MemoryConnection.func_74428_b(MemoryConnection.java:89)
	at net.minecraft.network.NetServerHandler.func_72570_d(NetServerHandler.java:141)
	at net.minecraft.network.NetworkListenThread.func_71747_b(NetworkListenThread.java:54)
	at net.minecraft.server.integrated.IntegratedServerListenThread.func_71747_b(IntegratedServerListenThread.java:109)
	at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:691)
	at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:587)
	at net.minecraft.server.integrated.IntegratedServer.func_71217_p(IntegratedServer.java:129)
	at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:484)
	at net.minecraft.server.ThreadMinecraftServer.run(SourceFile:583)