Part 1 of MrFranswa's Resident Evil-inspired Sven Co-op mission is set in a large mansion and the surrounding area, and features a complex plot inspired by the Resident Evil series as well as heavy use of Sven Co-op 3.0's model and sound-replacement features, with "New gruesome monsters to fight" and "An entirely new arsenal of firepower to use", etc.

There's a lot of download sites. Most you have to sign up for sadly.