Thought I would start the ball rolling with this - hopefully we can get a Route Building Sub if the mods would oblige and place this thread in there... DTG Alex dtg_jan if you could oblige. Anyhow first part of the process for most of us is getting the DEM (terrain) data in there. Found this page which refers to the general UE4 process which presumably is not dis-similar to the custom TSW editor: UDK | TerrainsFromDEMs (unrealengine.com)
I think everyone can agree blender will be the normal for 3D modeling: I highly recommend Guru's donut tutorial to learn the ropes if you haven't already - https://youtube.com/playlist?list=PLjEaoINr3zgFX8ZsChQVQsuDSjEqdWMAD&si=gCxCQuDBK3FTUSJy EDIT: aswell as that Google map AI's are a must, setting them up are simple and it's just a case of changing it for TSW4 - I'd actually argue this is more important then DEM. there are millions of tutorials but this is a good general up to date one.
I'll look into setting up the forums to have a dedicated space for Editor related discussions. I am also hoping to create resources that showcase the basics of creating assets, implementation into the Editor and ideally bringing in members of our development teams who can talk us through setting up timetables and other more advanced features. Community resource sharing will be a massive part of helping the PC Editor ecosystem thrive, and we'll look into supporting that in the best way we can!