Hey ! It's actually pretty simple passing though the basics. The engine (Aquedi4, see
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) works as a drop in, basically place the editor in the same place as the game exe and you're good to edit whatever you want. We have a partially translated editor to English, if you're interested (we didn't published it publicly so far).
The concepts are very similar to RPG maker, using "flows" like RPG maker uses RPG Maker script. Modding is actually quite easy, but really version dependant. Your mod won't work on newer or older version of the engine, nor newer or any change of the map. It's one mod for one game version, and if the game change you certainly need to re-create the mod. It's fairly bad, but at least it's quite simple to edit game (similar to RPG maker games)
You will still need knowledge on how to edit pictures (pixel art) and a lot of patience to navigate though the endless menus of the editor. I hugely respect people who do manual (non MTL) translations and mods on Aquedi4, it's really a busy ant task...