Rigid body objects may go insane if project is moved into 2.75 if they have a rigid body joint,
solution? add new object, grab data from old, delete old mesh.
and the fix
feels kinda neat to find a bug, find the cause, then work around it before anyone can even look at the
bug
Not an excuse to simply decide to have the bug stay unfixed, otherwise youโre projecting the idea that instead of the devs. fixing the bugs, you expect everyone else to workaround it as well.
I reported the issue(first) and then looked into what exactly as going on, then worked around it
https://developer.blender.org/T45396
cheers