I have Nokia icon on developer preview 8.1. For some reason I went to open twitter last night and the icon was dark and clicked on it and it would load or anything. I restarted the phone, still nothing, I deleted the app to try and reinstall it, but I go to the marketplace and there is no option to download it anymore, I can still view the app in windows store but can't download it. Any ideas why? Just happened out of no where.