Ouch. Yeah, I've heard not-so-great things about the Ambassador too. It's like many of the big, mid-range hotels in BKK: not well kept-up, and thus badly in need of renovations (or even just a good cleaning).

My rule for BKK is that you're generally better off going for the low end (a basic and clean guesthouse for $10; something a little nicer for up to $40) or the high end (luxury at a fraction of what you'd pay in Europe or North America).

Better luck next time,
Michael