THIS IS A (COMPLETELY JUSTIFIED) RANT, BE WARNED!
I like a particular set of sliding doors in the built-in assets, I don’t like the walls. So I build a custom wall with a doorway, and I just want to use the doors in that doorway. But I can’t because we can’t access most built-in static meshes. So I extract those meshes with an external tool, export them as “custom” meshes, copy and paste the material from the original doors onto the meshes. Set up my door, everything looks good… Project won’t cook because of “illegal references”.
Why limit us in such a shortsighted way? Now I have to extract the textures (or make new ones), remake the materials, waste time, bloat the size of my project, use more server resources, for… what exactly? So people can’t “illegally” use built-in assets?
This is a wholly unnecessary, artificial, and wasteful hurdle to put before creators.