i use soundforge or cool edit (which i beleive is audition now), into 8/16 bar loops, then i chop the loop/s further in my mpc, however i have the 1k so maybe doing all your chops in DAW maybe easier as for the 500's screen size set bak... there is a program for windows called bluebox, which enebles you to assign/save your chops into a program for your mpc...
peace