Help with Admidio

Hi all,

I am trying to install Admidio to help my local traditional chinese martial arts club, and i am stuck.
When i install the software, either .zip based or docker container, i am left with a partional-only funcional application.
I can login into the app without any issues, but on the left pane of the screen, where there should be some menu, there is not.
I created several users other than admin, even can use the modules if i type them by hand in the url but they are missing.
Also tried to add a menu, and when i go to "menu level" the tab is mandatory, but the dropdown is empty.

Has anyone gone thru this before?
Thanks so much for your help