Works like a charm, thanks so much.

I'm suspecting that you're right with the reasoning behind the cause of the sudden change. I was thinking along the same lines, but couldn't find much reference online that steered me towards the reasons.

I also appreciate the style guides, but I'm afraid that this code belongs to one of my coworkers, and fixing it only fell to me since I'm handling the Linux conversion. I seem to be the only person here that really wants to do any kind of 'best practice' style of coding. The segment of code I posted was ripped out of a much larger piece of software which likely would have made you cringe if you'd seen it. ;)

UPDATE: Bah. Still this thing taunts me. If you go a little farther down in the code, there's another MainWindow Frame that gets created, $PartStep. Everything packs and resizes properly up until that appears. Now it's just that section, but I still have to grab the bottom of the window and pull it down until it's tall enough to show that section.

UPDATE TO THE UPDATE: Seems the solution to this was to move the point where $PartStep got created. I moved the creation/pack up to where the others got created, and then left the population part where it was, and that seemed to take care of the problem.