Looking at all your posts.
I have never seen this many errors from anyone.
And I have been here a long time with many versions over the years..
The current version seems to be the most error free for a install..
Could it be you need to start over with the install.
The first would be the test script located at:https://www.ubbwiki.com/latest/system-requirements-test/central
Install and run it to be sure your site is compatible with the software.
Then follow the install directions exactly.:https://www.ubbcentral.com/doc_install.php
Following all the file /folder permissions.
Some hosts don't allow 777 so if that is true try 775
Plus read the readme file in the downloaded zip file from the members area.
The default character set is utf8 set in the generic.php language file on line 2.
In almost all cases you would create a new database using utf8 if not the you need to edit the language file to match.