I have used a lot of game editors in my time, starting with the Unlimited Adventures program based on the Gold Box D&D games, and frankly from what I can see I have come to a conclusion.
If the devs wanted the DOS editor to be widely used and see lots of mods (aka adventures either in the main official story or stand alone adventures), then they have failed. This is not a tool for the majority of possible users out there. Simply looking at what has to be done to create a custom adventure tells me that. I realize that some raving fanbois who have advanced technical skills will rant that anyone can do it if they want to, but the real goal of an editor like this is to bring about a stream of new player made content that keeps the game alive in the market and brings in fresh customers. Most people will look at the editor and back off, which is why there are so few mod projects available after six months on the market. As a comparison, the NWN1 editor, which was only marginally user friendly, gave the community the tools that resulted in a massive wave of content in the first six months after NWN was released.
Right off the bat I see suggest two improvements:
1) Automate the creation of custom modules
2) Add editor wizards for guiding the new user through complex tasks.
If the editor package is left in it's current state then there will not be enough content to keep people playing the game in the long term.
I am starting the process of learning the editor and will be able to produce some new content for the game, but I have experience going back over 20 years in deciphering cryptic editiing tools. Most people lack that kind of experience.