Thanks for the replies! Finally back home and unpacked for a few weeks. Hopefully I'll be able to dive into further analyzing the problem and adjusting the slide if necessary. Again, it looks like it has gotten skewed or dropped in the rear maybe .25" - 0.5" measured by the directions from Power Gear in the link above, so a slight vertical adjustment may well be in order. I did notice that above the front vertical adjustment bolts, there seemed to be scratches where the adjustment bolts "used" to touch....looks like the slide slipped slightly at some point and the direction of the drag marks would go with the direction of the sag according to the seal crush on both side and bottom wiper seals.
fcooper: - I had looked at the kitchen rollers, but they seem to be pretty well fixed in place. The one beneath the kitchen cabinets rolls freely (not touching the underneath of the slide floor) when the slide is all the way out. Is it supposed to be free at that point? The primary rollers, that are accessed from the basement bins, seem to be functioning fine and the pinion gears appear to mesh with the racks perfectly.