Bill, thanks for the concise review.
While I can't say that I'm excited by the subject, Horse and Musket game mechanics are always of interest to me. I would welcome additional info on how the game processes shooting and melee, and handles key situations from Line of Sight to movement across terrain, etc.
On the one hand, much has been done before and very little is new. Still it sounds like the authors have an interesting and simple turn sequence, so perhaps they did other things with a fresh approach?