make sure the CM is on, and USB plugged into both pc/cm.
insert our cd, but if the instal program starts up, exit it.
go to device manager (start>control panel (in classic mode)>system>hardware>device manager) the usb will either be under 'network adapters' or other devices with a conflict (normally a question mark) alongside it.
double click on it, and click on reinstall driver. go for an automatic install, select to search in the cd drive.
if it fails to find it, the path to the driver is CDdrive:\drivers\ambit - browse to it and install...
that should be job done