There is no where to walk to get to AK from ASMu. You'd have to walk on the shoulder of the road. Take the bus or drive your car. Much safer. You might be able to walk to the McD's. I think there is a sidewalk along that roadway.
There is a sidewalk to McDonald's. I walked from AS Movies to McDonald's and then to Blizzard Beach... and then to Coronado Springs. The sidewalk does not appear to have been constructed only recently. There are many resort staff members who use the sidewalk everyday. There is even a unique timed "Walk - Don't Walk" pedestrian signal at that busy Buena Vista Blvd. intersection.
ASMu to McD is EASY walking distance (20 minutes tops). Enjoy!
ASMu to McDonalds, or even to Blizzard Beach is doable, however don't attempt to walk to AK.... it is a 6 lane road, no sidewalks and cars are known to fly through there. Take the bus or drive... much faster and safer!!!!