You have set the build option of your “map.tmx” file to “copy”, but this will just copy the file (untouched) to the output directory.
You need to set the build option to “Build” to actually create a .xnb file.
Regarding to the other post you received a “NullReferenceException” in the “TiledMapTilesetImporter”, when trying to build the map.tmx file, so it seems that some important object inside the TiledMapTilesetImporter need to be instantiated first.
I don’t know what your map.tmx file contains, but maybe there is something missing whereby this important object can’t be created.
But i’m just speculating, as I don’t know the TiledMapTilesetImporter class.
I tried it but sadly changed nothing. Also tried creating a map using v1.1.5.
But I found out that it has something to do with the tileset. When I import the tileset from the test into my game it works but when I try mine it stops working. So I checked the demo tiles and they all where in One so I threw mine in one file as well and somehow it works