JohnP- you're on the right track here.
In the case of spoilerons, I would suggest playing around with the following:
four sets of hafl-ailerons -
in the config file, the aileron motions are "limited" to - left deflection "up" =0 and right deflection down=0.
the r_aileron_top (located just over the l_aileron_bottom) and l_aileron_top (located just over the raileron_bottom) have their pivots/axis rotated 180-deg in z direction so the l_aileron_top "down" is visually "up"....
in the same corresponding pivot points, tag small parts, usually almost invisible cubes .01 on the sid, as spoilers, animate their action as spoilers (l_spoiler_up, l_spoiler_down ... link the corrseponding parts (l_spoiler_down parent of l_aileron_down; l_spoiler_up the parent of r_spoiler_up ...etc)
Alternatively,you could tag the ailerons "lever_stick_right_left" and keyframe the aileron animations directly
I haven't tried this out so some experimentation may be needed to get the right effect (maybe you make the ailerons the parents of the "spolers"...
BTW - FSDS2 can make complex motions, just as gmax can, with the correct tags and keyframes, and with conditional displays.
After looking at microsoft's 747, and seeing exactly how they set up there motion, I would suggest setting up two sets of spoilers on the wing. This would be done by making one set and copying and pasting another set over the first set. Set one, you would label as spoilers(keyframe animation) and the second set I would label as an airleon. The spoilers work off the / key and the