Part of the problem was that I don't have proper mounting brackets for the tracks. All the proper brackets I could find are intended for .. well, hanging actual barn doors, so they are to sit flush against a wall parallel to the track. Since the track is perpendicular to the joists, I just drilled the track and screwed it right into the joists. Problem is, it doesn't matter how many times I measure, I have to cut (or in this case, drill) one time more than the measurements. Measure once, cut twice. Measure twice, cut .. er, three times. Apparently I suck at measuring.
So there was a lot of drilling into the track going on tonight.