SC, i feel for you man, Ive had exactly the same problem. Just wanted to throw my AB away anyhoos, heres my routine to clean my AB, I hope it helps you.
1stly after finishing spraying, i never leave the thing more than 15mins with paint in it. Then i tip the remains back into the paint pot or away, its up to you. Then i fill with Laquer thinners (I use acrylics) to about 5mm of depth. Then using an old brush, i stir the crap out of the paint cup. This really agitates the paint and can get right down the needle. Then hold a cloth over the end and fire the trigger. Be carefull as the paint will try to come back out of the pot. This should clean the tip. Tip this away, wipe out the cup with some lint free cloth or kitchen roll. Then add a drop of airbrush cleaner and blow that through. I use a cheapo AB cleaner that is slightly detergenty. This lubes everything in there.
For a deeper clean after you got to the stage of just being about to put the AB cleaner in, remove the needle and give it a wipe lengthwise with some old scotchbrite ensuring theres no paint on it anywhere. Using Franks Optivisor check the tip is not bent. This can play havoc with your spray patterns. Next remove the tip shroud and make sure theres no paint build up in there. Then remove the tip. These are the swine. If i have one that might have a build up in, (Hold to a light source and check) i use a pin from the GF or needle and gently scrape away any muck. Then leave the thing in some Laquer thinner for an hour or so and repeat the pin thing.
There you go, it all sounds long winded, but i can give the AB a quick clean after everytime im spraying and with the stuff at hand, takes about a minute.
Good luck and let me know how you get on.
...Guy