
The only setting you can check is in FS2002 for assignments. Check to see what is assigned for the spoilers. As a rule the "/" key is the one that wil manually control the spoilers. Question, Will the spoilers manually deploy? The only thing on your throttle quardrant that will move is the spoiler lever and not the throttles. When reverse thrust is applied, they will down from the idle position.
If you have air ed you could look at the air.cfg file and look around line 337(Spoiler Auto Deploy Available). This statement should be "True".
Hope this helps a little, if not post again and I will try another approach.
P.S. When arming the spoilers are you moving the Spoiler lever to the Arm position?