Here is a Windows Batch file. Open a text (notepad) document and paste this in. Then name it something like MakeMap.bat
Double clicking it should create you a new map file. Unfortunately I have not found a quicky utility for Windows so you can view it right away so I have to start a game with the map in order to see it. If you download the windows version of ImageMagick then you could view it right away.
Code:
cd c:\Progra~1\dominions3
set MAP=muddle
set SIZE= 1000 1000
set PROVS= 100
set GCOL1= 50 100 50 240
set SCOL1= 20 50 80 250
set BCOL1= 111 191 111 100
set SBCOL1= 111 191 111 100
set OTHR= --seapart 20 --mountpart 50 --farmpart 20 --mapnoise 110
set COMMANDS= --makemap %MAP% --mapsize %SIZE% --mapprov %PROVS% --mapaa %OTHR% --mapgcol %GCOL1% --mapscol %SCOL1% --mapbcol %BCOL1% --mapsbcol %SBCOL1%
del c:\Progra~1\dominions3\maps\%map%*
c:\Progra~1\dominions3\dom3.exe -T %COMMANDS%