The winning bid must be the lowest unique bid up to the 199,000th block.
You should clarify whether bids in block 199k itself are counted. i.e. is it "up to" or "up to and including" block 199k?
Also, is it allowed to send multiple bets in a single transaction?
If I make a transaction with 2 outputs, one of 0.1 and one of 0.2, both to the bet address, does that count as two entries (0.1 and 0.2) or one entry of 0.3?
It would be better (from a spam reduction point of view) if you treated it as 2 bets. Then I can make 2 bets with one transaction and not pollute the blockchain quite so much.