For maps you have two options:
1. Regular object:
You can make your level in 3ds Max and export it to a .3ds or .x, set up collision, stick the player inside and you're ready to go. Cartography Shop exports to .x and would work fine, especially since its set up for making levels out of cubes (much like MGS).
2. BSP:
Last I heard this was a little difficult to set up, but more DBPro updates are rolling around the corner so this may be different, and you can always search the forums. You can make these in Valve Hammer Editor, Worldcraft, or QuArK.
Unless you see something you like otherwise I would just stick to using 3ds Max to make your levels.
Crazy Donut Productions, Current Project: Project Starbuks
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