Some days ago we changed our Samba shares for the first time in this year. This lead to some shares being unavailable due to the blacklist for share paths which seems to have not been working until http://errata.software-univention.de/ucs/4.4/132.html. I recognize it is a good idea to have this blacklist, but it would have been nice to get a notice about it during the upgrade. Maybe it could even have recognized that there are shares which will become blacklisted and asked if they should be put on the whitelist?
I feel your pain; been bitten by the same issue in the past. That path blacklist is a rather opaque feature of Univention. It’s not at all obvious why a share doesn’t show up, unfortunately.