@advocatux and @Flohack thank you ! There were no further problems and i can acces my OPO in the filemanager. Now i feel like a highclass-hacker although i have absolutly no clue what i have done to my phone

Second attempt worked. OPO is successfully flashed with 16.04/rc without updating the installer. Many thanks to all involved in UT!

Hi,
just for fun (and maybe others have the same issue) i want to report a solved problem: After flashing my OPO with 16.04/rc i want to revive my exitisting Telegram Account. When i tapped the Icon Telegram started and want me to insert my Phone-number. I tried several times and nothing happens. Just the circle spinning...So i deinstalled Telegram and reinstalled it from OpenStore (the unoffical Version, not the WebApp).No deleting of special folders: And then? No asking for numbers, my Account recovered to health.

@fla yes, maybe there is still a lot work to do, but a lot of work is done already! Many thanks to all the kind persons who are making this possible!