The version compatibility has settled down now. It's almost at a stable release so I'd pick up the most recent and go with that.

You can set up a campaign file or a map file. The map file is easier to import into an existing campaign. However the campaign can hold more information. Campaign files hold information about the rules system - such as what kind of light sources you have. So you can set up a square torch lighting area in a campaign file. However a map file doesn't contain rules system information (the feeling is that a map file is more low level and should be importable into anything).

I set these map packs up before the map export function existed so I've stuck with the campaign files. I'm thinking about playing with map import/export when maptool hits final.

If you want to check one out then I'd suggest the Low River pack. It's got a few light sources and it's a classic dungeon setting. I think it covers all the main points. Let me know if you have any questions - and if you don't get an answer then send me an email. I don't manage to read all the new posts on the forum as often as I'd like.