The newest setpoint 2.60 + widcomm 5.0.1.2500 can recognize my mx 900 without logitech hub. Most important, my wish came true, setpoint
allow to customize button assignments without using bulky hub. Yehaaa !!!
Step by step:
1) Download setpoint 2.6 (included widcomm) at logitech site.
2) (Optional) Remove previous setpoint, widcomm. Restart.
3) Run installer. Don't press "Finish" button.
4) Explorer into "c:\documents and settings\administrator\Local settings\Temp" (i use "administrator" username, replace that username by yours). Search for a directory contains 3 subdirs: khal, Redist, Widcomm.
5) Copy Widcomm folder to another location. Now you can press "Finish". I think no need to restart.
6) Install widcomm.
7) Use the attachment program "license patcher" to generate a license.dat and a license.reg file. Select "TM350" in the drop down box. Press patch. It will put those files in the same folder.
8) Copy license.dat to "program files\widcomm\...", to whatever folders that contains bttray.exe
9) Import license.reg to registry, it will remove the "trial period" nag screen.
10) Execute bttray.exe. Right click on bluetooth icon, Start.
11) Restart. Done.
12) Now setpoint allow you to customize buttons. In other to specify functions for each application, please download uberoption
here. Install it, then a miracle come true

The attached file: "patcher 1.7" is downloaded from gsmhosting forum. This
thread.