Ok, deleted config and made changes through GUI. I should have it set up so that any block should be viable for them to spawn on, but yet they refuse to spawn on BOP blocks.
From what I understand, if I leave a blank entry in their blocks thing, they should be able to spawn on any type of block, right?
Edit: So what I find is happening is that when I change anything through the GUI, it automatically reverts to default on relaunch. Definitely explains the issues I have been having.