it was actually painfully hard. we ended up with a very elegant solution though... Blogger has a set of widgets, but we introduce some new ones (like a 'Photos' widget or an 'Events' widget). These sort of inherit from existing ones (by transforming their templates), so designers only have to code html+css for the standard 'Blog' widget and the others are inferred

btw, we had to make a custom blogger xml interpreter from scratch

Thanks for the info. Now I have an urge to create an open source standard for site themes based on Blogger templates or something else. Some things might be too specific (like the way a typical blog is formated) but lots of the elements could certainly be constructed in a way that they'd be interchangeable across totally different kinds of sites. Maybe Google Gadgets addresses part of this problem. Hmmm...