Edit/rename or delete tags in WKO+
Once you enter a tag in WKO+, it's there forever: there is no way to delete a tag. Similarly, if you misspell a tag, there is currently no way to edit or rename that tag (you must instead create another tag that is correctly spelled).
My suggestion: like just about every other program out there that uses tags, allow renaming or deleting tags. Look at 1Password if you want some ideas for how this should be implemented.