Not sure if this is the same issue, but... I was also experiencing greyed-out network readings (both wifi and cell) on my Galaxy Nexus GSM. Apparently google apps is incompatible between 10.1 and 10.2, which causes the phone to be unable to talk to google's servers (which is what a "blue" network icon means).
This silly forum won't let me post links to help other users, so to find the instructions/background, google for "how do i update cyanogenmod faqs" and check out the "Update from 10.1 to 10.2" post in the first link on the cyanogenmod forum. (Think of it like a treasure hunt.)
Updating my gapps addon fixed this issue for me. YMMV.