When you say that I can do the test run, Do you mean that I can just make a only lands map in right size{ like the one you enclosed in the basic map folder }, and put it into my_campaign folder... put the Japanese map_Heights I just made in the folder as well. then fire up the game?
But, Don't we need to make the TXT and the other TGA as well for running up the game?
You do need text files and other tga's as well. My basic map folder is an example of the minimum file content you need.

You can either resize those tga's to the sizes required for your map, or make your own 'blank' ones using the same colours. The only two tga's you need any content on apart from the 'blank' colour are the map_regions.tga and the map_heights.tga.

If you resize my map_regions.tga to the size required for your map, you can use my descr_regions.txt, descr_strat.txt, ....regions_and_settlement_names.txt etc. Just make sure you position the block of cities which are currently in the bottom left corner over an area that will be land. Also make sure you remember to check that the height and width in descr_terrain.txt are correct for your map_regions.tga size.

If resizing the map_regions.tga remember to use method that does not blur colours - and check that each region has a 1pixel black dot for its city after resizing.