To play INFR1 (that was patched for SCP) with FS_Open on Win:
1. Open the FS Launcher, pick the FSOpen version you want to use.
2. In MOD, pick the Inferno folder (make sure in the INFR1 mod.ini, you DO NOT have MediaVPs of any version working with it, they will NOT work together).
3. I dunno, INFR1 worked with .14 on me.