When you clicked next and these errors came up, did you still have the fields to enter your database connection information?
I also had errors, but I just pushed on and then it asked to re change some permissions after the installation, and things are working fine. I also installed the ad-free, and didn't enter my license until post-installation.
I also had errors, but I just pushed on and then it asked to re change some permissions after the installation, and things are working fine. I also installed the ad-free, and didn't enter my license until post-installation.