FX Crown Continuum and the new Superlite Barrel

Thank you for taking the time to make and share those videos. 

Two questions: 

1) Are these superlite barrels (the whole assembly) backwards compatible with older Crown actions? 

2) Will you have these superlite barrels available for sale separately? (for said people who already own a Crown and might want a barrel change/upgrade) 
 
I'm interested as to what is actually holding the barrel liner in place on this assembly, given that the nut is loose on the liner? I had initially assumed that it would be epoxied in place or something. 

Is it just compression of those orings clamping down or something else not seen on the video inside the rest of the assembly that clamps down when the nut is tightened up?