Time for the next step in evolution and learn to make DVD menus.

I have been trying out DVD-Lab Pro, however I noticed some disturbing things, first, the Menu Render Motion makes noticabely worse quality video with buttons embedded, so I tried to export buttons to PNG, lo and behold it exported as 720x540, something that should never happen, neither PAL, not NTSC uses 540 resolution, pon closer inspection the Menu workspace is displayed at resolution 960x540, as if this was up- or down-scaled to PAL, or NTSC respectively.

So few points.
1. Is it possible to adjust the menu reoslution to more accurately reflect PAL resolution?
2. Since the Render Motion makes a worse quality video, should I perhaps prerender the menu video in Vegas?
3. The chapters menu, is it possible to make it that the background video and audio play and the "next page" changes the thumbnails to next set, but the audio and video is not affected, or if it requires a sifferent submenu, is it posible, to keep the background AV in sync, so that when next set of thumbnails is clicked on, the submenu will resume playing AV at the same time, the first submenu with first set jumped to next submenu?
4. Should I prerender the submenus in Vegas with thumbnails and songnames and in DLP add only buttons there?

If nothing can be done wth the 540 ridiculousness, what other authoring program can you recommend that will do the trick and keep the proper Sampel Aspect Ratio, as had been discussed in this thread: