I personally cant even see the difference in Deco Layers. If I cant notice it, it must be hard to find, meaning you have to look for it, so just stop looking for it and you'll be happy? :P
Just use the SET tool. Its like the old painting mode. And the color choosing screen is like the old one. And PLEASE DO NOT SHOUT LIKE THIS. GERD DERNGIT.
I just did a little work on improving the deco editor now. I made it so that whenever you select a color (like with the color box or the preset colors), it will automatically select SET for you. I still think the editor now is fine how it is (except smudge and the thing I just fixed), I just want it better.
... that one line was harder to make than it looks
With other improvements I want to make (I hope for official but if not only my mod will get the improvements), I might undo that later. I want it so if you press 'b', it will bring you to the deco menu and save which tools you are currently using and set them to SET, CLR and color picker instead. It will also pause it. When you press 'b' again it will go back to what you had. I won't make the box show up all the time, what we have now works good. I will make it taller again though, fix the black colors on the bottom (select them, it's lying, they are really whites), add alpha editing again, show the hex value the color in the picker, make the color box change to represent what you will really get as you modify alpha and brightness, and fix smudge. All of this is what it's like in my mod.