Try downloading it again, I made a few bugfixes just a minute ago.
I tried exactally what you described, and it works with the latest version on my machine.
So, if you try it with the latest version and still doesn't work:
- Tell me what version of windows you use
- Look in the argmap folder for a file called "errors.txt". If it's there, tell me what it says.
What should happen if everything is working, when you select the file, some windows should come up (it's processing the map) and it should take around 10 seconds or so. Wait a while just to be sure wether it works or not.
[edit] I uploaded a new version, yet again. The errors.txt file is now called output.txt