ASMo is fully opened and All-Star Music opened up on 9/16, but I'm not clear if all of the buildings opened since many people reported they had been shifted around to other resorts the weeks before opening.
The wait for Movies was long one night after Epcot and All-Star Music had no line, and we hopped on it and then walked back to Movies. Other than that buses were fine (we only stayed at Movies for 2 nights and used buses for one rope drop morning since the second day we transferred to another resort and used Lyft). I did use buses for hopping on two days and had no issues at all.
Magical Express will run through the year's end. As of Jan 1, this service will end. Keep in mind, you may not get the traditional bus between now and then. For arrival we did (shared with 3 other resorts) and DD and I were brought back to MCO on a van that held maybe 8-10 passengers. There was just us on the bus, the other person was a no-show. In June, we had the regular DME bus for return. So it'll depend upon demand at your arrival or departure time.
Edited to add: It was recently announced All-Star Sports will be closed indefinitely. It was supposed to reopen in December I think.