I've discovered that it's only the start module that doesn't work. If you select individual modules, it seems to be ok. I decided to load and old copy of Nero 7 which seems to be fine.
Generally, I like Win 7 so far. It does seem to be quite stable so far, and UAC is far less annoying than in Vista. I thought I'd want to reinstate the Quicklaunch toolbar on the taskbar, but so far I haven't bothered, so maybe it's not as necessary as I thought!