So - some more info on the Mission Editor we posted here vs. the Advanced Editor. The Mission Editor is intended to be less intimidating than the Advanced one for users who haven't worked with map making software before. Both are there, however, in order to allow users who know what they're doing or are willing to put the time in to learn to really deck their maps out. But yeah - the Mission Editor is more for people who have never used editor software and don't think they have the skill to make maps.
A big part of that is essentially putting on blinders - many of the more dangerous or complex settings aren't accessible in the Mission Editor, so it's far less likely that you'll get yourself into a bind with corrupt or unworkable stuff. That, of course, also means that you don't have access to a lot of things you'd perhaps like to do, like weather effects or moving objects. It's a tradeoff made acceptable by the inclusion of the advanced editor.
A bigger part, however, is doing some things automatically - we fill in a bunch of the obscure settings and add obscure objects you need in place, so you can focus on laying out a space. I've been working on tutorial documentation, and the workflow essentially goes like this:
1 - Open the editor
2 - Pick which mission type and base environment you want to use
3 - add walls and lights and stuff using the 2-click (click wall piece you want, click in world to place one) interface you see in the image we posted
4 - Build lighting, test your map, save
5 - Publish to workshop
If you're so inclined, you can therefore make a map by simply laying out walls - no crazy editor experience required. It's made to mostly match the workflow and keys you'd use in the Advanced Editor, so the intent is that you get comfortable enough to easily jump into the advanced editor and make more complex stuff.
And since I haven't been terribly explicit about the Advanced Editor, it's the tool we use. It's Unreal Editor 3, with our game code and assets - which means that just about any and every tutorial you find for Unreal Engine or Unreal Development Kit (UDK) translates directly. You can make and place your own meshes, particles, materials, BSP structures, or use ours; you can also use Kismet (visual scripting) to make any kind of mission you can think of. I've used it to make a mission where you have a VIP, you turn off AA batteries (or shut down the whole grid), then pick an extract point to set off a signaling flare, then hold out until a helicopter flies in to that spot and the VIP jumps on the rope ladder. And it wasn't near as complex as you could get. The only major difference is that I can locally mess with the assets we made in ways that you won't be able to directly - you won't be able to alter the floor pieces we use in our maps, for instance, in such a way that all other players fall through. You'd have to open one of our maps, copy our stuff, and manipulate that to troll people.
All this freedom comes with a lot of risk for inappropriate content, of course. We're relying more on the community to vote stuff up or down this time, as well as mods - it's not going to be as heavily controlled as it was when the Mission Depot was a thing. For the most part though we wanted to clear the way as much as possible for people to make incredible stuff for other players, so we'll do what we can to cut down on farming maps and offensive imagery without infringing on creator freedom too much.
We're planning on having some of the Level Designers (and myself) stream ourselves using the editor (both types) on Twitch or something in the days following the mission editor release, and probably sporadically afterward too. That would let someone watch us work while also asking questions - questions we can show the answer to, rather than just describe. In any case, we don't want there to be any excuse for anyone to say "I want to make a map, but I don't know how."