Well, the editor remained as is for some time now because I don't have free time to work on it anymore. I made it while I was unemployed so I had plenty of time to spend on it. I had no previous programming experience so I learned as I went along. Starting idea was just to have something that will help me create girl files, but since other people liked it I gradually added functionality to edit all resource files from the game. I filled info with what I knew to date and it mostly remained that way since.
Currently I simply don't have time to sift through forum to try to fill these blanks. Last few updates were just bare minimum for editor to be able to support new WM features as I don't have time for more.
But that's why I also post links to source of the editor, which I tried to comment as much as I could. If need be someone else can update it and make it support new stuff, or make tweaks like this. Although better option would be to simply make new editor as this one is pretty much hack job. At time I was thinking of rewriting from scratch myself, but since I got a job that it doesn't leave me much time, even at weekends or hollydays, that idea got scraped.
It will probably stay as is, I might only update if some major bug appears or some new functionality needs to be added, but as far old stuff goes it will stay as is.
Traits and their descriptions have been discussed few times. Editor doesn't store any trait descriptions, descriptions get read from their file the same as traits themselves because this way if some new traits get added editor would be able to use them too, no update would be necessary which wouldn't be the case if they were hardcoded in the editor. You can open traits file in editor, edit trait descriptions and they will be reflected in the editor.