I see what you mean now. At least 4033 could handle an explorer reset.
Longhorn has dx9 capable drivers built in for the D600's mobility radeon 9000. All 3D functionality work right out of the box, but DCE still won't show the borders.
DCE, 3D View tiles, and DXDiag on the D600. I noticed 4032's explorer leaks much more than 4033's. In addition, the preview pane doesn't display WinFS options or the oversized icon on the left when browsing certain folders(e.g. opening shared documents or users documents from My Computer), was fixed in 4033. So in all reality 4032 is essentially a buggier 4033.
The build I truly wish we had was 4030.lab06. Though it isn't too different from 4033 or 4032, it does represent the earliest known incarnation of m6 and its trademark plex(xp styled back/forward buttons, no title text in explorer title bar, blended navigation bar with title bar).