The FotRSU mod, like most other "super mods", uses the <Ctrl><Enter> key combination to shoot the torpedoes. The two keys used together help to eliminate accidentally shooting torpedoes when you are hammering away on the <+> key of the numpad, and accidentally hit the <Enter> key there. Just be sure and open your torpedo tube doors before shooting, else you will miss behind. Consult the "SH4_Q-Ref_Card_Back.jpg" and "SH4_Q-Ref_Card_Front.jpg" files in the root of the game folder for other keyboard short-cut changes implemented in FotRSU:
