> Explorer cannot keep the display configuration per folder that
> I set it - not if I edit a parent folder (with the 'inherit'
> checkbox cleared, obviously).

I think this is a long-running bug from XP and earlier. The "per-folder" configuration stores configuration entries for a fixed maximum number of folders, which I imagine you are more likely to have exceeded if you are running Vista.

There may be a registry hack, but I just turn the feature off because it annoys me when it works.