Can't create Admin-Acc. Timeout and redirect to create Admin-Acc

I am completely new on Linux so bear with me please.

I recently made an unraid server. Currently on version 6.11.1.
I now wanted to install Nextcloud on it. I read quite a few “How to” and watched YT Videos on this.

Now to my problem:
I downloaded and installed the Mariadb today (09.11.2022)
After that I downloaded nextcloud (linuxserver’s Repository)

Now if I go to the WebUI i should create an Admin-Acc.
I fill in all my Data

and click on Install, after a few Seconds comes “504 Gateway Time-out”
In the Videos I watched they did say this could hapen, just go to unraid and open a new WebUI.
So I did and Nextcloud asks again to create an Admin-Acc…

I don’t get any other Errors, so what did I do wrong?

This seems to me as being an Unraid-Problem.

Running NC on unraid could lead to some strange behaviours (reading through the forum). I don’t know how to solve this.

Maybe it would be better running a docker? Why not an AiO-Docker? Maybe unraid deals better with docker conmtainers? - Well again: I got my impression about unraid from reading about problems with unread from the forum. There might be a ton of users running NC well on that, though. I just wanted to put that out. :wink:

I run that as Docker, NC and the MariaDB.

On unraid there is a NC-AIO Version, but as I read the discription it seems to need much Know-How on Linux, wich I don’t have.