I think you can't use something like print screen button.
The problem is the editor does not have a full-screen function. When I try to maximize the editor window, it expands but the map keeps the same resolution.
I still don't know how he can capture full maps like these showcases.
Yeah, I hadn't really considered ways of saving the resulting maps, outside of taking a bunch of screenshots and stitching them together.
A .PNG export shouldn't be too hard. I'll see what I can do.