Thanks for the reply! We got the game working on an older Mac laptop. But here are details for future reference.
Did not work on this newer MackBook Air running OS version 10.13.6, as described in the previous post.
Everything worked great on this MacBook Pro from 2009 :D running OS version 10.11.6.
Really appreciate you offering to look into the issue but I'm good, happy the kids are playing on the older computer.