I believe the AllStars have been added to the resorts that allow SW to use the RAC system. Not exactly sure when that takes effect though.
Every single person arriving at MCO is entitled to ride the DME bus to their resort and then back to the airport...as long as the resort is owned by Disney. SoG, S/D are not owned by Disney so are not eligible for DME.
In order to use the RAC (remote airline checkin) system, you must be flying home on a participating airline. That list tends to change occaionally, so check the thread stickied for this pupose. SW is generally not considered a participating airline, but you can use the RAC system for checking your luggage and getting boarding passes at the resort at POP and the AllStars now. SW and Disney are looking to possibly implement this at other resorts down the road. But again, it only matters what airline you are on for the flight home, and that is only an issue when checkin luggage at the resort...it has absolutely nothing to do with riding the DME bus to, or from, your Disney owned resort.