Problem understanding Blenders Paint transparency

Hi all,
first forgive me my bad rusty english first.
I try to paint my model without external programs. Yes i can paint UV-tex in external programs, but i really like that Blender unite so many different programs.
This is what i want to do http://www.polycount.com/forum/showthread.php?t=73559
This is what i get http://www.blendpolis.de/download/file.php?id=92753&sid=746706421c53e9402bd99c22b908b250&mode=view.
I dont get the correct settings. I use the “Draw” option (Tex draw…), i made so many different alphas to test it out with hard and soft edges. Ist the strenth setting the only option to paint tranparent?
I use the Layer system and my first (bottom) (occ map) is on multiply, all other on mix.
Should i use my tabletpen (pressure sensitivy)?
Im also interested to buy a good book that covers only the paint/material section.
Any suggestions?
Greetings Stefan

Is it a silly question? Miss i something.
Greets Stefan