Dear Hans,
Please look through this link containing the instruction for TZ plus gallery plugin.
Then make sure that you followed all as we did.
In case you did the same, but it was still stuck there, please send an email to support@templaza.com or add new ticket (Sending us your site and admin account, we'll help you check.) here:
https://www.templaza.com/tz_membership/addticket.html
Brds,
Bao Bui