Yes, I used to use kext helper a long time ago. you would be better off learning the command lines.

Make a backup of the 10.6.8 iousbfamily.kext.

Delete the 10.6.8 iousbfamily.kext from the system/library/extensions folder.

Then drop the 10.6.3 iousbfamily.kext file into the same s/l/e directory.
then issue these commands

then set the proper permissions for the file be executing the commands below in terminal:

cd /system/library/extensions
sudo chmod 755 iousbfamily.kext
sudo chown root:wheel iousbfamily.kext

Reboot.

I hope things work for you. Half of my USB stuff was not working at all (mouse,trackball, bluetooth dongle) when I had 10.6.8 iousbfamily.kext installed. I hope this fix's it. You may want to do some research on the hardware ID for VIA usb card. That may need to be added to a kext file, or like I said the via usb card may be incompatible.

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