why do some mods do this?

[Tidus Klein]

I play my game with several mods mainly RCS build aid, B9, Kerbal engineer, and procedural fairings. give or take kethane and KAS.

and I found out that some times when in the editors when you click on a part that has already been attached to a plane/rocket, the game glitches and doesn't allow you to put it back on. and the more you try to put it back on the more the COM and other indicators moves only to eventually show the part in the normal attached fashion only no where close to being physically attached.

Now im no noob and I know no one supports mods and guarantees perfect operation I just want to know if anyone as had the same thing happen to them, because the only way that I know how to fix it is to ether, load the craft up again, or is some serious cases where not even the save/launch/quit buttons work is to close the game completely.

PS for some reason also any ship I make with B9 lags like buns but not in the normal stop and go jittery fashion of KSP im talking smooth lag like the entire word is in slow mo, this really stumped me, not even panning under the ship helps:confused:.

Edited November 8, 2013 by Tidus Klein

[Bobhendly]

Ive had a similar situation with some older mods.. My debug log was stacked with stack overflows.