This mkaes the Spawn Vehicles mod compatible with Helios' Spawn Menu.
Edit the line in the file FSGAME.LTX from this:
$game_data$ = false| true| $fs_root$| gamedata
$game_data$ = true| true| $fs_root$| gamedata
Unpack the "gamedata" folder from the archive in your main folder (where you found fsgame.ltx)