This is not a ubb issue but a Apache issue.
Never change the case on a ubb script file because Apache will not find it.
Assuming you have the default ubbt prefix in your MYSQL which it looks like you do.
Looking at the first table it should look like:
ubbt_ADDRESS_BOOK
then the next should be
ubbt_ADMIN_LOG
And so on.
I don't even want to get into asp pages. I used them, two years later I am still going through hoops to fix redirects.
As far as external files the habit to use lower case is not the issue.
say you made a home page index.html that is fine.
But if you add a reference to that page somewhere else say in a island and you typed Index.html. Windows will work fine.
But Apache will bark back and say the file does not exist. Because the first letter is upper case.
Also If you have a home page and your url goes to say Ubbthreads.php instead of ubbthreads.php it will not work because of Apache thinks it is a different file.
The funny part in my previous example about the three index.html files. You can have all three in the same folder but when you download a backup it will just overwrite each one.
Just a FYI
