We booked two separate vacations throught skyauction. The first one was at Cypress Pointe GV, the second at Sheraton Vistana. I requested non-smoking at both resorts(after I won the auction), but only Cypress had non-smoking rooms. Vistana does not have any rooms designated as non-smoking. Can you believe it? Anyway, we just returned, and the room was not smokey. They said they put an air purifier in it prior to our arrival.
I would recommend checking with the resort before you book through skyauction, as that seems to be the best bet. Skyauction does not seem to handle any special requests, but the resorts have been willing to work with us after we have booked the trip.
Good Luck!