Place the dm_sfac.pk4 into your 'Doom3\base\' folder.
Notes:
Well this is basicly my first attempt at a decent mp map for doom3. It's pretty small compared to the stock maps that came with the game, but it has some perks. I hope people enjoy playing it as much as I did designing it, and I expect to release more as time goes by.
Comments/Questions, email me at spacecat@sbcglobal.net