Every tool has its shortcomings and WadAuthor is no exception. It lacks one feature that would really be helpful: Creating a wad file with multiple maps. You can edit a multi-map wad file, but you cannot create one. This tutorial gives a simple work around.
The first set is to create a simple Doom 1 or Doom 2 map using one sector and one player start as illustrated in Figure 1. In order for this to work correctly, you must selected the Doom1 or Doom2 WCF configuration files. Do not create a ZDoom file. I will be using Wintex to merge the files later in this tutorial and Wintex cannot handle ZDoom wads correctly.
You do not need to worry about textures or sector heights at this time. This is just to create the placeholder.
The first map will probably Map01 or E1M1. Save the file as D1.wad. Now right click on map edit screen and select the Map Name option from the popup menu. The Map Name dialog will be displayed as in Figure 2.
Change the name to 2 and save the file as D2.wad. Continue this process until you have the desired number of maps that you want in your wad file.
Next, start Wintex and select either Doom or Doom2. What you are going to do is merge these files together into one wad. I usually pick map 1 as the target map and merge the others into it. In Wintex the Join PWADS button is used to merge wads as shown in Figure 3.
The wads listed in the top list are the maps that will be inserted into the wads listed in the bottom list. In Figure 3 apoch2.wad (map E1M2) will be inserted into apoch1.wad (map E1M1).
If you are editing Doom1 or Doom2, then that's all there is. Load the merged wad file (apoch1.wad) into WA and both maps will be present.
For a ZDoom map, one additional step is necessary. Use the ZWADCONV.EXE program to convert the file to ZDoom format: ZWADCONV.EXE apoch1.wad apoch.wad. The newly converted file, apoch.wad can be now editied in native ZDoom format. In WA, load the ZDoom configuration file and start editing.
To edit a particular map in WA use the Select Map option from the View menu.