I have an AP from WDW but am from CA and also inquired about using our passes. I called the number in the booklet that came with my AP and they said there is absolutely no way you can use your WDW AP in DL. Bummer!
But I read on the boards of someone using their WDW passes in DL. Maybe that person can explain how!
I think you can somehow convert WDW park hoppers to DL tickets but you can't use WDW APs at DL. There is another thread on this subject somewhere recently. Maybe someone else knows exactly where it is and can direct you to it better than i can.
I asked this question previously and got the answer that I could exchange days from my WDW 10 day parkhoppers for day passes at
DL. That is what I plan to do in August of next year.
You take your ticket to the turnstyles, they have to go call WDW to confirm there are days left and they come back and give you a DL ticket. We've done that a couple of times before, but I can't remember if we got a park-hopper or a 1-park ticket... seems like it would have been a PH