Mac compile of engine loads blank large project

When moving from dead windows computer to Mac M1 Max 32gb, on load all was fine till the terrain, materials whichever or both, started flickering, almost unusable- so I compiiled from source, ran editor, browsed for project, it loaded fine, but the project was empty!,all with no errors, what would cause such a thing >? o_0

Granted, even though the source is 5.3.2, it had to open a copy, but a copy of a working project, should load, so I dont get it ???

thx