Before going straight to use-maps, make one melee map. It has no triggers at all, so you get the experience of a map working from terrain and placement alone - everything later sits on top of that.
Terrain Symmetry, in the middle of the left panel, means drawing half of it.
| Mirror-X | Left to right. |
|---|---|
| Mirror-Y | Top to bottom. |
| Mirror-XY | Through the centre point. |
| Tile / Isom. Rot | Rotational, about square tiles or about isometric ones. |
Without at least two Start Locations the map will not run at all. It is under Neutral in the Units layer - not the one in Unit Sprites or Pure Sprites - and one per player.
A melee map only takes start locations, Player 12's resources and critters. If you want a neutral building, the way in is a Unit Sprite placed as Player 12.
Units and sprites