No, I've had Zedge for quite some time and have never had a problem with it. Have you tried restarting your N7 since the problem began? If not, try that first.
Did you download it from Google Play or another source? If another source, try uninstalling again, restart your N7, then install from Google Play if possible.
If no luck, then contact the developer. I suppose you could also try a factory reset of your N7, but that's kind of a last resort, big hassle solution. Better to contact the dev first.