We had a small accident.. my wife was in big hurry to get out of the
garage, and she started backing the car from within the garage as the
door was still opening. The door opened enough for the rear of the car
to get out, but the power antenna caught the garage door and broke. Once
we had the car back in, we noticed the following damages
1) Some of the rollers had come off the tracks
2) The metal string (?) has come off the pulley on one side of the door,
causing the door to be hanging in a tilted position (torsion spring
mechanism at the top/middle of the door).

With the help of a friend, I have managed to fix both of the above -
friend had some knowledge about how to work the torsion spring).
HOWEVER, now I notice cracks on 3 of the 4 sections of the door - about
2 inches long.. near where the sections curl up and meet each other.
This must have happened when the door was unbalanced (one side pully
working and the other side hanging by it's own weight).. maybe something
else, like the impact).

Now how do I fix these cracks? I am not much good at welding / brazing
and I have already messed up the paint near one of the cracks (about
2"x2" area) trying to braze it. Is this repairable? Or must I replace
all sections of the door? The rest of the door seems structurally just
fine.. auto opener works - everything is ok. But the sections now have
cracks! 8 (

Thanks!