cannot modify built in engine - problem UE5-0

Hi,
I am using “Modeling Tools Editor Mode” plugin. I am trying to fix UV maps on meshes, I used all of available tolls like: Unwrap, Project, XFormUV even AutoUV. But every time I press accept there is error called “cannot modify built in engine”.

There is only option to fix it: I have to recreate my entire project using shapes from modeling mode pannel (All previes meshes in my project comes from “quick add to the project button”) . On those meshes I can influence on UV maps.

But pls tell me there is something I can do to safe my work