Open Source with Marketplace Assets


I’ve been working a long time on a project to view & create Virtual Worlds ingame (for all platforms VR & non-vr) using UE4. Think the Matrix, meets Oasis (ready player one), meets Sims .

Anyway, I’ve been toying with the idea to release it open source, however I bought some assets of the market place.
I found other projects that are open source and used market place assets.
These all seem to cook the binaries they bought and distribute that separately (e.g a mega or google drive link).
For example: GitHub - microsoft/AirSim: Open source simulator for autonomous vehicles built on Unreal Engine / Unity, from Microsoft AI & Research

In case of AirSim they seem to supply a compiled .umap, thus the user can use the map, but not edit it.
Now in my case I would like the contributors to still allow changes to the map.

Note: I could not find any documentation on how to setup this specific scenario.

Anyway I currently have 3 questions:
Question 1: How do I setup my project in such a way that contributes can also access the map with bought assets if they open my project with the Unreal Editor
(Note: A pre-requisite is that they have access to the Unreal Editor repository on of course)

Question 2a: What would be the preferred way to setup such a project?
I was thinking:

  • Main Private Repo (contains all code & assets uncooked)
    |-> Public Repo (= Main repo without bought assets, the missing assets are loaded in binary form external source)
    |-> Contributor forks
    Question 2b: Are there scripts / programs that help automate this process for unreal projects?
    (e.g keep all repositories in sync; so when assets get added -> auto cook to binary & push to external source)