If you install the new optimized apps with the installer exactly as directed, it flushes all the WUs with this error: "19-Jul-2009 02:08:56 [SETI@home] [error] No app version for result: windows_intelx86 608."  276 WUs all in error.   If you stop Boinc, run the installer, edit app_info.xml to duplicate the <app_version>
        <app_name>setiathome_enhanced</app_name>
        <version_num>603</version_num>
...
section and change the versiion to 603, and restart Boinc, it does not flush the WUs, but it won't run any CUDA WUs either.  It just sits there keeping 4 CPUs busy and the GPU idle.  This is true even if I edit the client_state.xml file to make some of the <workunit>s version 608.  Boinc changes it back to 603.  I have spent over 4 hours fooling with this, and still it will not use the GPU.  I believe that it is waiting for 608 WUs, but I can't be sure.  With the S@H server in its present screwed up state, downloading any 608 WUs is impossible.  Why won't the new client process version 603 WUs?   Thanks for all your hard work.