Sounds like you're doing everything correctly. Did you mess with the port settings in the CPS? I think its up top under "file". The CPS might be set to a USB port you're not using. (Don't have it on this PC otherwise I would look) You might have to change them or try different USB ports on the PC.
The port setting is important. If you don't tell the computer what port to use, serial or USB, it will never find the radio.
It is also better to start the radio software up and get it running before you make the connection to the radio. If the drivers are not set up already in the software, it won't work. So letting the software start up and be ready for the radio, when you attempt to make the radio connection, the software should install the driver needed if it has never done that before. The software is contained within the CPS.
The other item to be aware of is the computer giving out with the audio tones that it sees the interface cable when you connect it to the computer. It should all ready be connected to the radio first.
Depending on the cable your using, it could be the round mic type connector that would plug into the round mic connector looking connection on the faceplate of the radio or the DB connector on the radio. No RIB box is required for these cables. The accessory connector is probably a serial connection and you would need to set the software accordingly. However, there is USB connections there and you could make your own cable if needed. I have done this before.
Let us know how you make out.
