What does the rulebook say?

Assume the following situation in a tournament. The players are having a rook+king (white) vs bishop+king (black) endgame, and white's time expires. After several hours browsing the detailed FIDE rulebook of chess, from what I understood, it seemed that the side with no time left will only lose if there's a possible checkmate position for the other side. That is, if you can set up a legal position with the black bishop giving a checkmate to white (despite him being the better side with an exchange up), black wins. If no such position exists, white comes away with a draw.

So, question #1: Am I understanding the rules correctly?

Question #2: Is this situation a win for black, or a draw? Because I've tried to set up a mate with the bishop, but failed. Having said that, I still might have overlooked a mate position. Can you guys come up with one?

Thanks in advance for your help.

1. You are correct under FIDE rules. USCF rules are different and the result would be a draw unless a checkmate could be forced.

2. I can't find one either