No you have to go to UA check in desk
Not the way to do it either, especially if majority on flying is on UA, you should have booked the flight on UA. Besides 2 direct flights (UA) a day to Houston from Edmonton, dealing with Calgary and their joke transborder system is a unneeded PITA
With a UA flight you can auto checkin, change seats as well
Booking that sort of flight on AC seems a self inflected waste of time, besides you can credit AC/AE so why book on them ?