extra build up of yeast can clog the air lines. Which is why most people use a sump so it doesn't get into the tank. The line coming out of your bubble checker, (this is a bottle correct) do you have the line on the inside of the bottle cut just below the lid?
You seem to be having a heck of a time getting up and running. This shouldn't be such an effort really. Maybe take a look at some of the tutorials out there and go with one of them?
The seals on your bottle caps (the thin tough plastic membrane/wafer between the bottom of the cap and the lip of the bottle top), the holes you make in them (use the interference fit IE: smaller-than-the-airline-diameter-hole and slant cut the tip of the airline to be able to grab and pull it through the hole with a pair of pliers) are all vitally important to get correct. If any of these escape points are less than perfect you're going to lose CO2 (and pressure) and the system just won't work.