Well, I tried this update several times, but so far no luck. I'm on T-Mo USA.
I removed the T-Mo theme and Vendor.xml, it loads fine and runs great. After I reboot the device (after re-installing any app from App Store) the theme goes wonky, i.e. it is back to the white screen (same as with the T-Mo theme) and I can't get it to work any more. When I check the installed CODs with BBSAK, the standard net_rim_theme_BlackBerry6_480x360_b_01 (18.104.22.1688) is still installed and is the only one on the device. I've done an upgrade as well as a clean install and keep getting the same.
I'm trying a clean install one more time, re-installing apps one at a time with a reboot each time, to see what will cause this problem. But if anyone else has already run into this or knows of a fix, I'd very much like to hear it!