Quote from WinstonTJ:
It depends on how you enter the ticker.
F9 = CMDY button on Bloomy. If you hit CL1 CMDY <GO> that is the NYMEX front month crude contract. If you hit CL1 COMB CMDY <GO> that is the combined (like NBBO) price.
Just hit CL1 CMDY DES <GO> you will be able to see the two tickers for the combined and exchange specific contracts.
Also - if you hit Alt+L on the bloomberg with a normal keyboard it'll bring up a screen of the keys from the terminal keyboard that you can select with a mouse, etc.