Thanks Justin!
I managed to exchange existing tile sets in your rpg example

but i could not manage to import new ones and i have problems understanding the auto tile format (relating to the actual tiles) and defining which tiles I have.
Also, how do i link the auto tile lines in the gme.xml to the png's?
I really don’t know where to start.
Now comes the crazy part:I would like to add a shadow on top of this and have from each tile 3 versions which are randomly picked to show some variation.
I try to achieve something like this:

With a tile set something like this:

I guess i am asking for too much without understanding it.
Thats why i would offer a payment but i am obviously also very thankful without.
Cheers!