I don't understand the coolant bleeder/tank system

[kk2002s]

I use a 6 gal pancake compressor and a UView. I think that is probably the smallest you could go. I did 2 Distilled water flushes and then filled with 50/50 pink stuff
I felt like I had to run the purge valve a couple cooling cycles anyways as I was not familiar with the temp behavior after this and new WP and low temp thermo replace.

The hardest part here in NJ is getting rid of the stuff, 12 gallons. Auto parts stores don't take it. Finally had a House hold recycling day where the county takes things like paint and antifreeze

I would like to know better how one uses the Uview with a full system to help remove any potential trapped air.
Anyone done Vacuum on a full system???
I have just started seeing condensation under trunk lid and I had a drop or 2 come out the overflow after driving an hour and half. It's been 4-5k miles since all the coolant work with no issues. Temps run cool
I have a new tank as of last Dec (2015),WP, thermo Flush. I had put an '04' cap on 3 years ago.
I just order a new cap to see if that is it