Bifold door hardware help.

We just moved into a home and when the painters did the walls, they took down our mirrored metal bifold doors and we are having problems putting them back up. The tracks were bent but I've been able to mostly re-align them. The biggest problem is tightening the stationary bracket that holds the upper pivot rod to the upper track. The bracket tightens to the track with a flanged nut. The nut rides below the track and (I guess) is supposed to snug to the track and hold the bracket in position. If I just snug the nut, the bracket slides. If I tighten the nut, it ends up partially slipping inside the track as shown in the pictures and the whole thing becomes a mess. Unfortunately I have no information on the brand of the doors.

The track measurements are approx 11/16 wide and high

Attached please find some added pictures of the pivot bracket. I'm not sure the screw and nut are assembled properly though.

The washer would add too much thickness, I already tried that. I ended up removing the nut and bolt entirely and getting a 1/4-20 screw with a head that was small enough to just fit inside the track. I put the pivot plate into the track and by tightening the screw, it forces the pivot plate against the track. This seens to work. Unfortunately, I cracked one of the mirrors on one of the doors.

Thanks for the advice but I've spent so much time and effort trying to fix these things that I've given up. The doors were sized and purchased for the opening prior to the installation of tile by the previous owner and we installed a floating floor on top of that so now, the top-bottom clearance is very tight and I don't want to spend time digging into the floor or routing out the top trim to recess the track. We're just going to replace everything with some other type of doors.