Not sure what's causing this, but it happens every time I load up a world

using 0.0.1.2 for both relocation and the fmp plugin and 1.1.0.24 for mrTJPCore

http://paste.ee/p/WFo5n

Looks like another mod you have is also hacking into the world renderer. Find out which one it is (by removing mods until it starts to work), and I'll see about fixing the compatibility between the two.

So it seems that Rotatable Blocks by AlgorithmX2 is the culprit. thanks for the help!

So, apparently Rotatable Blocks transforms the same "renderBlockByRenderType" method in it's transformer as ForgeRelocation.