You could use an older version of Krom's map editor, or use my MapToPro to make a .pro file of a .map file and then edit the pro file with Krom's editor
Or you could use Quage's map editor, I wouldn't really recommend that though
For MapToPro, copy and paste this link into your webbrowser
http://www.freewebs.com/knightsandmerchants/downloads/MapToPro.zip
Clicking it may not work. Right-click -> Open in new tab may work in some browsers, Save Link As may also work
Usage of maptopro: drag and drop a map file onto the program, it should generate the pro file automatically. You need the .NET 2.0 framework for it to work, you can get it here:
http://www.microsoft.com/downloads/details.aspx?FamilyID=0856EACB-4362-4B0D-8EDD-AAB15C5E04F5
Known issues: not all objects may be right, and terrain brushes will not behave properly. (both are fixable, but the program isn't popular enough for me to bother)