I do not agree.
IMHO your photos show that you have an airleak.


The before/after pump matters when you use festo cause there nature is to seal with presure and not suction.
The jetcat metal silver filter doesnt care if goes before or after ...just to be on the corect direction placed on the system


I always prime my system with the help of the pump at high power before conect it to the engine(just conect it back to the UAT)...and knocking the filter till i see no air coming in the lines..


sorry for my english