stacked cannons
As far as building strategy is concerned, I usually build all over the place, strategically of course,
especially on the inner areas of the corners.
On most maps there is a small delay when the comps hit the corners. If you figure the range of the weapon, plus that dely, you can usually get 3 extra hits in, per cannon.
By building in more than one spot, you ensure hits throughout the gameplay.
As far as how to build a map like this......
You don't share vision with anybody.
Place starting points in obscure locations.
Place map revealers for each human player.
And, you set up triggers that enable, and disable shared vision for each player respectively.
The last is done with one of the many special editors that are out today. There is a download address in my signature, if you need it.
For an example, I attached one of my conversions, you will see the shared vision triggers near the bottom of each players trigger screen.
If you try the map, it's a little more intence than most, no delays to build.
You will see that I altered the terain so that stacking is manditory, and that placements are in strategic spots. As the game reaches about 2/3 the way, stacking ceases to be allowed. This is the games decision, not mine, I think it's because there is too much going on for the proper triggers to fire. It forces the players to buy heros, which I recommend anyway.
I seem to remeber a small glitch in the second phase of the dificulty triggers,
"choose fast", or it automatically sets for EZ.