Wow, that's really cool. I hadn't expected to see something of this sort! Perhaps Chris or Keith will be able to make the theme editor support creating new weather types, if it doesn't already. Awesome work.
Also, apologies for the weird attachment bug. We haven't been able to figure out what's causing it. Despite the 8 MB limit, it consistently refuses to let anyone upload files bigger than about 2 megabytes. I'm not sure how we can go about fixing this; it's definitely pretty frustrating.
Edit: I'm going to move this to the main forum to make it more visible (and, well, it's not a puzzle). If we start getting more themes, I'll probably put up a custom themes forum and move them all there.