Ships Breaks and drifts away after undocking, and things get weird.

[zhinghong]

Hello,

KSP version Mac 10.9.5, Steam, KSP 1.0.2.842

A detailed explanation: I docked two ships on orbit around eve, did refueling, quick saved, undocked, landed, then I quick loaded back to before undocking. this time, as soon as I undock, ships starts drifting, collides and parts start falling apart. if i do time warp, ships changes positions back to correct position after docking but the (undocked ship) part are messed up (please refer to last screenshots) , and when I get out of time warp, ships starts drifting away again. I tried disabling crossfeed, turning off rcs, sas, doing little burns, rotating ships, switching to other ships and back. The only thing that worked was decoupling the tank which the docking port is attached to causing the ships to separate, then unblocking the docking port. But I can't land the ship with this missing tank.

A screenshot attached

A .craft file or save files (save folder attached [default.zip])

ATTACHMENTS LINK: https://www.dropbox.com/sh/zvfzow2dlz0eax7/AAAzHdv3qB1C73zcaM8Y5Jo9a?dl=0