Hm those are the same symptoms I've have on my cable, I never connected it to CM7. (I've always had to tweak my nook cable to get it to work.)
At work I use my kindle's microUSB and I've never had any problems charging the nook. The speed is pretty quick as well.
One note about CM7 is the WIFI never turns off, the dev did this on purpose to have a quick connect time when the nook is woken up. I don't know if this has been fixed in the newer version of CM7.
Let us know if the new cable fixes the issue.