Copying all files into the demo folder on internal also didn't worked.
Everything below i'm doing on internal in demo folder:
Replacing debug.dat (demo, in built/game/) with full version did nothing (R3 demo stars and acts like it's demo).
Replacing debug.psarc (demo, in /packed/game/), same as above (R3 demo stars, and is a demo)
Replacing game.psarc (demo, in /packed/game/ ) with full version - black screen, freez.
So for now, NO GO, folks.