Kerbal Space Program

Ive a ship in interplantery space wich is incontrolable besides it has ec and kerbals on board. I cant do anything with it. When iam eva a kerbal via paw the nerv gets destroyed and the kerbal and the ship leaving kerbolsystem with the speed of light. If u quicksave and reload only the nerv apears. The ship was saved as subassembly with the nerv as rootpart and then put into an dockingport jr inside of an mk3 cargobay of an ssto. I could undock from the ssto and set a maneuver and burn it. Setup the next maneuver in 90 days and left it alone doing other stuf now i wanted to execute the maneuver and this happens