Credit goes to: SimoneT

Launch Xebra.
1)Select File->Open->OS ROM Image...
2)open your bios image
3)Select File->Open->CD ROM via SPTI...
4)open any file on it
5)Select Run->Run2(1-pass)
6)After a short gap the game start
Steps 1) and 2) are only required for the first use.
Ciao.

P.S.: On FF7 probably you can't see any files... no problems, make an ISO and:
3a)Select File->Open->CD ROM Image...
4a)open your image