Here’s a solution for x64 with the 4.60 setpoint drivers: http://forums.logitech.com/logitech/board/message?board.id=software_mice&thread.id=11017
direct link to the file: http://camel2.ck.tp.edu.tw/~danix/Setpoint.4.60.Windows.Server.2008.x64.CDDRV2.Patch.exe
This may help… it looks as if this guy got it working.