Thanks Sailor Steve, I should have put a note for manual install!

If you still have problems Chris, follow the instructions to create the final "SFX Pack 1.3 Standard" folder ready for JSGME, then simply go
into the "SFX Pack 1.3 Standard" folder & copy the data folder
on top of the "SilentHunterIII\data" folder & everything will go to it's correct spot!