Looking forward to the rules - shall definitely be getting them!
I'll try having a look at that page 17 - I think the problem was, that targeting speculative fire is normally an opposed roll (or otherwise depending on the targets Q) with negative modifiers - and when targeting the ground, you have no opponent with a Q - but I'll try reading again, and try to work my head around it.
I have an idea about making up some Mantic Forgefathers (dwarves in space) stats for FL (and I still have an unfinished Warzone-stats project), but maybe I'll make use of the Apocalypticum-rules instead (using the Forgefathers as some underground hi-tech vault mutant faction that comes out foraging now and then) - only imagination sets the limits