I have the same problem, but I am running the Linux version. I did not find a Linux version of the mod. Is there any other working arounds? I have tripulated mission returning from Eeloo, and they run out of fuel, so I built another ship for a rescue mission. This ships was too big to be launched on a single part so I docked the parts together on orbit, now I need to undock some parts. The ship won't make it without releasing the extra weight =(