I also noticed this same problem when maneuvering larger ships to dock, and I lost about half of a fuel resupply to random rcs firing before I could dock it. What happened was the rcs began firing semi-randomly, sending the tug and the scaffold careening into the station, before it eventually began accelerating uncontrollably away from the station and was lost.
However, when I was using one of my ‘tugs’, which are really just a fuel tank with a bunch of rcs stuck on the side, to move one of the scaffolds I was using to expand my station when I encountered an issue. Recently I’ve also been able to realize my dream of having a space station with the automated transition window and rendezvous mechanics (I have found it does have trouble with elliptical orbits, so a perfectly circular orbit provides best results). This game is incredibly good, and I’ve sunk many hours into it.
