try this, Impove found a version of HTC Home for the 800W. i tried it on my pro and it works.
http://forum.ppcgeeks.com/showthread.php?t=32393&page=6
its the last post on that page. but skip the steps on installing the RealVGA. this version of HTC Home is meant to run at 128dpi which the Treo Pro already does.