Junker,
I feel your pain. I have just moved and I am the new guy here. For the most part I just keep my mouth shut and officiate my game. If they come in my area and we have a double whistle I take it to the table... if it wasn't a foul I let them live or die with it. Remember when the evaluator is looking at the tape or at the game they know who had a whistle and who didn't.
Keep doing those things that help you rise to the top. Same advice as everyone here has been giving...
As far as how to not step on toes in the pregame ask questions or give game situations you want their opinion on
works great! And of course adapt to how they do it as long as you aren't picking up bad habits.