[dogscoff]

Should be pretty easy to stop them opening warp points. Just take out all references to the warp point openy component in their design files. (Leave the warp closer in there though, so that they go around closing warp points like the isolationists they are) Of course if they should acquire a warp opener by gift/ trade/ theft (unlikely) then you can expect them to behave just the same...

But to answer your question, I know of no such mod. Doesn't mean there isn't one though.