Incident 1: Just cover the cards. Same thing happened to me in a tournament where I finished 3 spots out of the money...and that hand would have garenteed me a triple up too.
Incidents 2&3: I probably wouldn't tip them for a while. This kind of shit pisses me off to the nth degree. In both incidents, I am calling the floorperson over and gettng everything straightened out without even talking to the dealer. For the dealer to take the word of one player over another's is idiotic. I'm the only one I trust to be paying attention to the action when I am involved...I rarely trust the dealers anymore. Too many mistakes. It's all about bringing th floor over as an impartial judge IMO. It's their job, make them work for it.
And if they come over and get everything straightened out, give them a tip before you leave...trust me, this always gives you the benefit of the doubt when it comes to anything they have to put a decision to.