No, non-mods cannot create RPGs, though they can create clan-contained (only your clan) RPGs if you already belong to one. These have to be created in your clan's forum board, of course.
If you do not belong to a clan and you do have a good idea, perhaps you could privately contact one of the mods and submit your idea so they can take it into consideration. Of course I'm just assuming at this point, so you would have to check with one of the mods first.
"If anything in this life is certain, if history has taught us anything, it is that you can kill anyone." - Michael Corleone