Hi Blade! I have 3.4 enabled on top of a fresh install of my original CD of SF. I don't know for sure that 3.4 works with Steam SF, although if 2.2/JCM does, hopefully it should, and if done with JSGME can be backed out if it doesn't. 3.4 did not work (many missions CTD on loading) with a previous non-clean install. Multiple installs are the ideal and it seems easy to just copy a complete un-modded install to a fresh folder - the sim seems to be self-contained. Never tried that with the steam install, though. Otherwise, it's one mod at a time!