Several years ago, I had an old AHM Rivarossi GG1 locomotive that was giving me runaway problems. It was one of my first conversions and I was using an HC-1 at the time. I sent the loco to Tim, who added some capacitors to the motor and that solved the problem. Today, that engine is one of my best runners and one of my favorites.
Like Bill, I also had a picture disappear from my HC-2, which I also sent to Tim. We still don't know hat caused that to happen.
I have also experienced some beta testing oddities which were resolved prior to the release versions.