Apologies in advance if this shouldn't be in the CX forum.

I've got an itinerary flying roundtrip on CX from YVR-HKG-XMN. I typically use my Alaska MP FF for CX flights, but the HKG-XMN leg is in CX Dragon which do not accrue miles on ASMP. I noticed that in the CX website, it looks like it allows me to apply different FF#'s by leg, so I was thinking of adding my AA FF on the Dragon legs. Has anyone done this before and had any issues? It's not many miles, so I wouldn't want to cause any complications for a low set of miles.

Thanks.