WIP - Modular Underground Tunnels

I am gradually approaching the completion of work on a new major project - Modular Underground Tunnels for Unreal Engine. The project is being made specifically for the Unreal Marketplace.
This project will contain a large number of modular underground architecture and props, as well as underground vehicles.
A distinctive feature, in comparison with my previous works, will be deeply customizable modular blueprints and high detail of the environment, a large number of objects for detailing.
Now the main architecture of the scene has already been completed, almost all 3D objects have been modeled and textured, the final touches on filling the scene and working with decals and materials for drawing on the vertices remain.
I think it's will be my largest 3D environment project in recent years, made entirely from scratch.