The Steam install is fine, just a few "gotchas" to look-out for, which is why I keep a bone-Stock copy in the Library folder, and make copies of that to "paste" into other folders that I name after the mod, such that my Steam / SteamApps / Common folder has:
1. Silent Hunter Wolves of the Pacific
2. SH4 FotRSU
3. SH4 TMO
etc., below it. I also used the Steam app on my computer, and "
Add non-Steam games to a Library". From that, you can rename the "sh4.exe" that shows up on the Steam menu, and you can create a desktop shortcut to it. Makes it much easier to start the game, and if it needs to, it can go through the Steam license check and (usually) never fails to start...
You could also install that disk version on the same computer, just to a different folder, but again, NOT in a "Program Files" folder. Myself, I have three versions of SH4 (four if I could ever find my original v1.x disk) on three different computers, and any time I can talk my sons into playing, we can do multi-missions on the home network. They don't like to get sunk though...
