Hola Henry, Pura Vida!
The CLX will do best in a larger room, but smaller ones could be made to work with enough acoustic treatments.
As for ideal, I'd guess that 20' wide by 30' deep would work best, but even a 16' wide room could do.
Homes in CR are usually concrete and very reverberant, so some acoustic treatment will be required regardless.
Tell us more about the proposed room.
I was just in CR a few weeks ago visiting friends and family, as I was born and lived there until 1984.