I'm going to give these a try when I get home... new mouseware & a more thorough testing of dx9a.
You guys do know you can use the drivers without installing mouseware right?
(Assuming you have winzip or similar installed... xp zip won't work)
Right click the Mouseware 9.76 exe and extract the files to your HD. Ex C:\Logitech
Uninstall your old Mouseware software
Go into device manager and upgrade the mouse driver and point to the logitech folder.
I did this once before and all my buttons worked fine on my dual optical... but the mouse seemed to skip more. Maybe I'll try again with these drivers.