Hi,
It's really simple to mod the game. Just download the source code from github, install a compatible unity editor version, and open DLS in unity. Once you're there, you can make whatever changes you want, but for the one we want, zooming in and out, you'll need to make a C# script. By chaning the camera's orthographic size, you can make the camera zoom in and out. Be sure to include the camera's child, or the input system won't work well.
Good luck, let me hear how it goes!