This documentation is relevant to WMWifiRouter version 1.20 and newer, and has been last updated to reflect the changes in version 1.25.
This option allows you to switch the USB port into any of the modes available on your device. Normal USB operation always uses the Rndis mode.
The Rndis mode is itself split up into two submodes: ActiveSync and Internet Sharing. The ActiveSync mode is the mode normally used when you have your mobile device connected to your computer. The Internet Sharing mode is used while routing over USB.