To add weight to Guillaume’s comments, my testing shows that Resolve (11 lite) always applies a studio to full range level change to ProRes 444 QT files.
Assimilate Scratch (play) does the same.
So does Nuke.
As Guillaume says; not such an insurmountable problem with Alexa footage, which is studio (legal) range, but anything full range will be clipped.
Media Composer 8 seems the only software that handles ProRes 444 correctly.
The way MC interpreted ProRes444 was corrected after V7.02, but was not documented anywhere.
Check for yourselves.
Herewith a clip containing superblack (0) and black (16):
https://courtyard.livedrive.com/item/08207bfc7cbf49a08cf2dc2721c33fc0
The superblack bars left and right of the grey bars are there when ingested into MC8.