Thought Jumblings before proceding

I've got a nice big piece of canvas (4 feet by 12 feet) to make a battle mat.   I'm going to cut it into 2 4x5 foot mats.

I've been thinking long and hard about painting it.  I really don't want to spread a ton of caulk over it, nor spend a lot of money on a ton of paint, which might also be a pain to spread.  I finally realized that, duh, the damned canvas is already sand-colored, so why on earth would I need to paint it to use for a Middle Eastern battle field?   I think I'll just draw on the rivers and swampy area that were present at the battle.   I don't know whether to draw on the hills or built some pieces, which we could then also use for our other games.

I heard some people use pastel crayons to draw on roads and rivers, maybe I should look into that.

I'm also trying to complete a draft of the rules for the game.   I need to finish them in order to test them, so I can see if the basing scheme will work on not.  I'm a little irritated that the formatting of the file gets a little wonky when I switch from the "Libre Office" word processor on Ubuntu to MS Word on my other computer or my work computer, and back again.   MS Word just insists on adding extra spacing to every thing which gets to be a hassle.

I think I have everything worked out for the basic rules, except for the unit movement rates and missile ranges, which I'll probably steal from some old miniatures rules sets from the 60's I bought last year.   Actually, I've stolen a lot from those systems, but am not going to just use them as written, since they are based off removing figures for casualties, and I want to avoid that and have fixed stands instead.