Formwork blocks on the foundation slab in a mortar bed or not?

I am also in favor of a separate thread :)

I would put in special effort in the front rows. Otherwise, it will come back to haunt you higher up.
I also don't believe that the panel is perfectly smooth, so you can just stack on it.

I am happy to create a separate topic here with an explanation of what I have done and corresponding pictures. I am still collecting some images and need some progress, and then I will gladly share it with you :)