Thnx Boroda, working nicely.
No, excepted words remain unchanged, not become lowercased (this is not obvious, but this is how plugin works).
Ah, that confused me too.
Maybe a second line of entry could be added to the panel so you'll have:
1. Except for words: . . . . .
This will apply casing rules on those words, so e.g. 'A' will become 'a' when 'Title Case' is set with the words "a, an, the, in, etc." as exceptions.
2. Exclude the words: . . . . .
This will exclude those words for any change at all. So UB40 will stay UB40, etc.