OK - usually when I post a question I find my own answer within minutes, so here's hoping...
I like to put videos in an html block on the side. As the blocks are small I use the ?d=160x160 or whatever resize method to get them to a small size - but I can't do this with a Moodle 2.0 block and I can't see how to do this. That massive "flow player" thingie won't budge and I am a bit stuck. What am I missing?