Glad damage was minimal and you are OK. You have any videos of it? I think your rig is awesome and I like watching it make sand runs.
I've seen it bend throttle blades and everything if the solenoid leaks into the engine and then they start it. I always make sure the bottle is off until the engine is started and if for some reason it gets left on between rounds I make sure to crank the engine over with the spark off and the throttle open to clear it out for several revolutions before I turn the spark back on. Obviously that isn't what happened to you.
Many people don't get their rotor phasing correct for when the retard is active during spray and then it can cause issues with timing breaking up or jumping to the wrong cylinders. It's one of the benefits of the DIS, unlimited timing changes with no rotor phasing to be concerned about.