Somebody recently posted a guide covering the basics here, though it does not cover tile objects (just select the “Insert Tile” tool instead of the “Insert Rectangle” tool, and select a tile in the tileset view before clicking the map):
Somebody recently posted a guide covering the basics here, though it does not cover tile objects (just select the “Insert Tile” tool instead of the “Insert Rectangle” tool, and select a tile in the tileset view before clicking the map):