Figure 1: Change Map Position
One of the better editors for DOS, in my opinion, is DMapEdit. In fact, in my early days of Doom editing, this was my editor of choice and I was one of the few that actually registered it. Now, Bruce A. Benko has added ZDoom (among other Doom variants) to this wonderful editor. This tutorial will get you started on setting up DMapEdit for ZDoom editing.
The first order of business is to set the proper paths for any game you may own. Open the file named dmapedit.ini in a text editor and look for the following lines:
doom path = c:\doom2\udoom doom 2 path = c:\doom2 heretic path = c:\doom2\heretic hexen path = c:\doom2\hexen *strife path = c:\strife zdoom path = c:\doom2\zdoomdos
Change these lines to reflect your own system setup. DO NOT end the path in a \. This will confuse DMapEdit. The asterisk (*) is a comment and you will need to comment out the games you don't have.
You will need to use the DOS version of ZDoom if you want to test your maps from DMapEdit. Just like WadAuthor, DMapEdit uses a converted Doom2 IWAD for the base wad. Use the conversion program that comes with ZDoom and convert your Doom2 wad to zdoomdme.wad
zwadconv.exe doom2.wad zdoomdme.wad
Be sure zdoomdme.wad is in your zdoomdos folder.
Start DMapEdit. Press the space bar to clear the greeting. In order to edit ZDoom maps, you need to put DME in ZDoom mode. Select the File menu item and Change Maps, as illustrated in Figure 1.
This will bring up the dialog illustrated in Figure 2.
At the top of the dialog in Figure 2 is a radio button called ZDoom Maps. This may read Doom, Doom2, etc, depending on your current setup. Selecting this radio button brings up the game type dialog as illustrated in Figure 3.
This dialog allows you to select the type of default map you want to create. The grayed out selections are games you do not have. You can also use this to convert a map from one type to another type. Keep in mind that once you convert a map to Hexen or ZDoom format, they cannot be converted back.
Following these steps will get you started on ZDoom editing in DMapEdit
Bruce sent along this additional information:
What I found to be helpful, is to click on the Load map from IWAD first if you are creating a brand new wad. This is just to be safe in case the wad that is loaded is in error (like the demo.wad released with the ZDoom editing stuff). If you are just adding a new level to your present wad then all should be well and the Load map from IWAD option won't be needed.
Example for changing between different game types:
If you are in Heretic editing game mode and wish to go to editing ZDoom
editing game mode, use the Load map from IWAD first. This loads the
Heretic actual game maps. Now, use the Change map position and when you
load the ZDoom maps the game maps from the IWAD (zdoomdme.wad) will be
loaded. Again, you don't have to do it this way, but it's a good habit
to get into. Now, you can load an actual PWAD (user) map and/or start
with a new map.
Note: Conversions are not done to ZDoom in version 4.2.1 yet. However, they will be in version 4.2.2 to be released in a couple of weeks.
Sources
DMapEdit reference by Bruce A. Benko.