You can try running some 1/4" carriage bolts along the top of the section, but that's more of a bandaid than a permanent fix. Once they start delaminating like then they just keep getting worse.
Uhh yeah man, those stop bolts keep things, much like what happened to you from happening. Call up the company and have them come out, also the reason your door came out of the tracks is too much spring tension and the opener over running its up limit.
I work for a small Overhead Door franchise so I may be a bit biased. But most doors, especially residential garage doors are pretty similar. As long as the installer knows what they are doing then you should be alright either way.
Came home after workin out of town for a week to find a package from SK, and one from RockAuto. Needless to say after opening my day was made and they have earned themselves a customer!
What he said, the slots are elongated so you can level the door. It looks like you have solid shafts, the hollow ones don't have keyways; instead everything is held in place by the set screws.
You guys are hell on my checkbook, I walked in for a couple vice-grips. Walked out with 5, a catfishing pole, gun case and a new rifle they are saving for me.