Konic v17 RC2 freezes on upgrade

I have Kodi 16.1 on both, a firetv an a windows pc. On both I install Kodi v17 RC2 and with the first start Kodi tries to migrate the databases and addons.
But when it shows “Add-on migration in progress” nothing happens a long time and then after some time kodi stopps working. Everytime I try it on both systems.

At the next start it seems that everything is okay, but Kodi finds no media data and hat problems with connecting to my nfs share.

What’s the matter? Is this behaviour known? Are there any “problem-add-ons” that cause this?!