Re: Advanced Notice - Update your client!
I'm on XP SP3 32bit with no antivirus (another machine on my network does that for me because I don't want to bog down my personal workstation scanning things that are clean). I have an Nvidia GeForce7300gt on Gigabyte GA-8KN ultra sli board and AMD 64 3500+ CPU with 4 gigs of ram installed (3.25 - 3.5 available). I have installed all windows updates, and there are no customizations to my user interface or default 3d options in the graphics driver control panel. Finally, the username on my workstation has full admin rights.
A friend of mine had the same problem. After we made sure to copy out his razor macros, profiles, and account stuff (my documents\ea games\uo *blah*\{anything}), I had him delete his razor folder and the UO folder from c:\program files. Then, using a file i had downloaded from tessascove's links page, we ran setup, which prompted to "uninstall" UO, despite that we had already deleted the folder, which is logical when you consider the registry. We finished that, re-executed the setup, then re-ran the patch. It patched up to full, and we installed razor.
For testing, we ran around a few cities and dungeons casting basic spells and practicing a little stealing, and we did not see any issues. Granted, this testing was not in depth, but the above method might work for some people, especially for those who have made "personalizations" to their client or any of the UO data files (Tree hack and otherwise...)