Hey there, I just experienced the same problem for a couple days and so I know how frustrating it is. Maybe I can help? I did a lot of research too, but for some reason I couldn't find anybody who had an answer. So here's what I did, and it worked:
After just simply turning my NC on and off ridiculously, I read on how to do a more permanent reboot by pressing the power button and the "n" button at the same time. When the screen fuzzed out, I said I wanted to go through with it, and gave it about five minutes to just sit there. After that, I turned it on normally and when everything had seemingly loaded, I went ahead and immediately made sure my WiFi was turned on. This way, I wouldn't have that as an excuse if anything didn't work. When I finally got all of that figured out, which didn't take long at all, the apps (DoodleJumpDeluxe, FTW) downloaded themselves and appeared on my home screen without me having to do anything. Maybe I just got lucky, but it was the strangest thing. It seems like that way to turn off the NC shouldn't always be done (?), according to my research, but I got so tired of waiting around staring at the gray lined boxes that I had to do something. I hope this helps, or maybe you found someone else to help.
FYI- When i rebooted it, the NC seemed a lil slow at first, so I would definitely give it time to come back up to speed. But, if this does keep occurring, I'll probably have to take it back, even though I take such great care of it
I was lucky, the hard power-off (holding the power button in and ignoring the "do you want to really do this" message, then waiting 5 minutes then powering back up) worined for me.