I downloaded both books, "Little Wars" and "Floor Games" with illustrations a couple of years ago. Quite interesting.
One thing though, I have read the Bluemenfield Gazette I think this is the spelling, a frw times and in it and in the rules for Little Wars, I read that they used a piece of string for measuring, as this seems to be a bit off here and there, I use a 24" - 3/8" wooden dowel marked at the 1 foot and 2 foot range, it is much easier to work with.
My other fuss with "Little Wars" is that it is the cannon that dominates the battlefield. I also use both cannon and musket fire. and in melee, I roll a 6-sided die for each klickie in combat. High number wins. After all combat is resolved, if one side looses more than half of the engaged klickies, they withdraw. If not both sides may attack again. Only 2 such bouts of melee per turn.
And so forth, and so on. I base my rules on a medieval ruleset called "Warlord". I have played many battles with 25mm metal figures using these rules.
-- da Hugh