I found this post and follwed the instructions of @maze
https://community.openhab.org/t/new-folder-structure/16526/83
OH2 runs now with the newest snapshot for nearly 10 hours.
But is there really no official statement or documentation on this? It appears a little bit strange to me that OH2 aims to “simplify” things in the areas of thing configuration and item definition by offering several UIs while other crucial functions like upgrading to the next version in Windows apparently are not functionally supported at all. Here users are forced again to search the web for hours, to experiment in the deep structure of their OH2 folder structure and make a best guess trial and error… 