If he already has a 36t on the front, he *has* to have a 110bcd crank, and just needs new chainings. I also don't know where you guys are getting that there is a short cage RD for apex, because according to SRAM there isn't:
http://www.sram.com/sram/road/produc...ear-derailleur


If you guys are going to give advice, at least know what you're talking about. He already has a compact, and has a RD that has a 32t capacity. If he wants to change his gearing, all he has to do is either put on a new chain and cassette, or new front chainrings, which may require shortening the chain.