What you show here is a Chinese mod or our editor I have released here with source code. You should go ask for the modified source code for this editor where you got this editor binary.
It would be nice world if those who make mods of programs they got from here offered their improvements they made to the program back here. But this being done by a Chinese, there is not much hope they will share. Still you could ask and if they give you the modified code, can you share it here.
Thanks
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That added panel at right is interesting but I am not a friend of reducing working map view area, particularly when as here it doesn't seem to add to map editing functionality (but that is just guessing from the screenshot you posted). Maybe if that panel could be hidden when not needed but even then.
The top part shows you where you are on the map (not really needed as you can easily zoom out to see your position on map) and even if that little red square was draggable and move the main view of the map around, it would still not add much to the ease of editing maps. On the contrary, the reduction of map view area it causes would actually have negative impact on it. Maybe the panel only shows the whole map view and that small red square is also your markup (same as those two large red outlines)?
The bottom half of the panel is more of a puzzle, I'd think all of that map info it shows you get from switching on info panel (pops up at mouse cursor), even if only for one particular tile at a time. I don't see how it is useful to have it shown like this.
But maybe there are other mods not shown in this screenshot that might give me ideas to implement them. Can you upload the editor binary or post link to where you got it.