EvilLoynis: Thorfin is on the right track with the RMG.TXT file, or TEMPLATES as they are better known by. However there are already several made up that have been very well tested and are pretty quick and easy to use.
First off to explain this in a better way. Templates are just guidelines for the Random Map Generator to use to help make better maps. You see the problem with it as it is is that pure random maps are very unbalanced just because of the randomness. Not to mention that you sometimes winded up with no way to get to your opponent, unless you got lucky and managed to learn Dimension Door or Fly (or artifact that gives Fly). I mean random is fun but not when you can't actually get at your enemy.
How to use them is quite simple after the first time you use or see it done.
The link below has about 20 templates ready for you to download and use. The majority of them are 1 on 1 as they were used for tournament play. They list the sizes they support and other things like if any towns are disabled, namely Conflux/Necro as these gave HUGE advantages.
http://toheroes.com/h3maps/Random.htm 1. Find the template you want to use click on it then choose Save As.
2. Copy the file and move it into the Heroes 3 Data file. Usual default path for the file below unless you chose somewhere else when installing.
C:\Program Files\3DO\Heroes 3 Complete\Data OR C:\Program Files\Gog.com\Heroes 3 Complete\Data
3 RENAME the file to "RMG" without the quotes.
4. Start a New Game, Single Scenario, choose Random Map and set your oprtions (keep in mind restrictions such as # of players and size of the template you chose) choose your town/hero or not as you prefer and hit begin.
*** To easily see that the template worked ounce you have started the game just hit the letter "i" to bring up the scenario information and you will see it says the name of the template used.
5. To choose a different template simply follow the steps again and delete the old RMG you no longer want to use.
Editing these templates is and advanced feature you may want to look into in the future. Best place to ask questions about that is on the Heroes Community web site.
Hope this helps you all.
I need more help. My H3 is not picking up the maps I put in or the random map generator. I am getting a message that says "Random_Map.h3m is not in the data" so I put that file from a template in data and it's still not getting it. Also RMG.What? Saving it as just RMG isn't telling me what file type I need.