I have the volume locked to my receiver with the volume punch through mode. How do I lock the channel up and down to my cabel receiver? HELP!!

I don't believe there is such a thing as a "channel lock". "Volume Punch-Thru" is indeed a special feature that allows the Volume of one device to appear automatically on some of the other devices. But there is no dedicated Channel Lock feature on the Cinema 7 as far as I know.

However, you can use "Key Mover" to do what you want with the Channel up/down buttons. Just "move" the cable receiver Channel Up/Down buttons, one at a time, to whatever other device(s) you want them to appear. You can read all about Key Mover, and all the other built-in programming functions of the Cinema 7, at [Link: hifi-remote.com]. Good luck!

Channel Lock is a feature of some UEIC remotes - for example the Millenium4 cable remote. It is not described in the documentation I've seen for the Cinema 7, but the documentation is so poor it omits many features.
Sometimes button sequences documented for one remote will work on other remotes. Here's the Millenium4 online documentation:
[Link: urcsupport.com]