There really is no point for this topic. Although the idea is to have many layers grouped to the gradient, it is alot more resourceheavy to use a gradient than to use the tilesets. Next, you only have 256 gradients, so that leaves room for a max of 256 distinct screens.
Thirdly, Nifflas gave 4 layers for the background, because most of the time, 4 really is enough. I haven't had the need for a 5th layer actually, and even if I had to, I could use Custom Objects to work on layers 4 to 7 too. Gives me 8 full layers of work.
Seriously, this topic is redundant and a to be honest, a bit pointless too.
Since there's no reason for this topic to exist in its current form, I'm going to lock it. Feel free to start a discussion about using gradients as replacements for layers in the Knytt Stories Level editing forum.