Download:

What you should do:
1. Crop and scale heightmap to the size that you want.

2. Adjust the brightness and contrast (or levels) to achieve a satisfactory result in the scenario editor (make sure the coasts are not too high).
(I personally prefer to copy sea (only black #000000 color) and paste it as a separate layer - then adjust color levels of land layer.)


How to place towns on map automatically:
1. Find cropped map coordinates (north, east, south and west edges) using Google Maps (right click and select "What's here?").
2. Go to Town list downloader tool and generate a list of towns.
3. Use McZapkie's Reproducible map generation tool (import_land) to import towns from generated list.