I have noticed that post the GDR3+Black update on my Lumia 920, some of the app installs are failing for no reason. It started with the Bing Translator app. It always completes the download but rolls back during installation giving an "Attention Required' message. I couldn't even completely uninstall the app as the icon is greyed out in the app list. It happened the same today when updating Temple Run 2 and 4Blend HDR. The file is fully downloaded but rolls back when it enters into installation. Other apps are installing fine though. Any ideas what causes this? I've tried clearing out the temp files but doesn't seem to help much.