I have a display problem on two different dev rigs, one a Dell Vostro 200 running XPSP2 with ATI X1300 and the other a Fujitsu Lifebook running XPMCESP2 with ATI Mobility Radeon X300 (both being ATI, might mean something).
The Shutdown Dialog displays correctly:

But the Logoff Dialog displays like this:

All the background images are .tga with proper trans settings.
The button images are both in the same .bmp format using magic pink trans.
Any ideas why the blue squares are showing up? It's not a highlight color I'm using anywhere. Both rigs support hardware accelerated PPX. [EDIT] The Fujitsu supports constant alpha only - has limited PPX support.
Thanks!