Placing. Drag a tag to move it. Click the map to add one: a region on Eriador; on Towerglan a project's plot, or a street name. Click a tag to rename or remove it. Save writes config.json through the local server.
Cutting.On Eriador, click each corner of a shape, then Finish (or Enter; Escape abandons it). A cut drops the terrain squares it holds; a keep holds them against a cut drawn around them; a sea paints the squares it holds in a flat ocean colour beneath the terrain, the Bay of Forochel say; a smudge paints the squares it holds that have no terrain from the ground around them, where the backdrop's lettering shows past the terrain's edge; a patch fills them with whole sections copied from a territory or area you name when you finish it, the Misty Mountains over the Gate of Moria say. Undo (or Ctrl+Z) takes back the last corner, or the last shape. Squares the last build dropped are shaded red. Click a shape to remove it. Nothing is kept until Save. Rebuild with build-game-map.mjs after saving.