If I am reading it right, this card will let Apex use non-virtual resources.
Apex is not prevented from including non-virtual resources in his deck, he is only prevented from installing them:
You cannot install non-virtual resources.
And per the FAQ, facedown cards have no type or subtype:
Facedown Runner Cards
Runner cards that are installed or turned facedown do not have a name, type or a subtype, and their abilities are not active.
So it seems Apex can install virtual resources facedown with his ability, then use Assimilator to flip them faceup, bypassing costs and install restrictions. I definitely want to use this to get an Aesop's Pawnshop into play!