should I put a number "5" to display 5 comments, or should it be text like "all". I realize it's not a supported theme, and I do appreciate the help.

Your choice. Normally all comments are shown, except you limit it yourself.

That I mentioned that it is unsupported is important as we are not familiar with those themes and they can do things differently than official one. If we check we check the official ones. So please always state the theme used first.