Ok, I've had quite a few requests for a map editor/steam-workshop support since the Early Access launch, to which I've invariably replied "I'll look into it later". Later has arrived, and I've looked into it and I'm now almost sure it'll be possible (in one way or another, details below). It might be a fair amount of work on my end to add support though, so I'd like to gauge interest first.
Here's what I think might be possible:
-If ZGA's going to support map creation/modding at all, it'll be using the Unreal Engine 4 editor (since making a custom level editor would take far too long).
-This would require you to download UE4, and the ZGA modules separately.
-The UE4 editor might be a bit more complicated to use than the custom level editors in other games (although never having used one, I couldn't say for sure), so you'd probably have to take some time to learn to use it, if you haven't already. That said, I think it's very easy to use for what it is and didn't find it at all difficult to learn the features needed for map creation, at least. UE4 is free to use now, so you could always download it to see what you think.
-You'd then be able to make maps for ZGA, using all the same assets and tools as I do.
-These maps could be exported from the unreal editor and uploaded to the steam-workshop
-Then, users could manually download maps from the workshop, and play online with them with others who downloaded the same map (I think it could be possible for me to make a system that automatically downloads the required maps when you try to join a server).
-Furthermore, the system by which you'd export maps from the UE4 editor is actually not limited just to maps, and could potentially be used for more general modding, such as game modes, weapons, modifiers or just about anything. I haven't made the game thus far with full on modding in mind though, so I'm not sure to what extent this will be possible yet.
I think that about covers it, although I'd need to look into this some more to be certain of any of this. Anyway, like I said before, I don't want to start on this unless I know people actually want it now, since I imagine it'll take several weeks during which there wouldn't be any progress on other parts of the game. Waiting until later in development is always a possibility too, of course.
So, please let me know if:
A) You'd like to see a steam workshop.
B) You'd actually like to create maps/mods for ZGA, even if it requires learning to use UE4 (or bits of it)
C) Or if you might be interested in either, but think it's best left until later in development.
Ask away if you've got any questions, don't forget to subscribe to the discussion if you do though!