I liked the idea, I think it is a good proof of concept. Stacking rocks in a meditative way, with gentle celtic type music. I managed to get to level 9.
I found it mechanically a bit frustrating to succeed, as I couldn't really place rocks how I wanted, and I think the overly rounded shapes of most of the rocks (other than the sort of stabby slabs), and their peculiar physics (one rock just randomly yeeted itself off the top of my 4 stack pile) made it hard to find much rhyme or reason to progression. I think something like this has to refine that mechanical aspect a bit more. Like I feel when you grab a rock, it shouldn’t become independent from the rocks above it, and have it possible to kind of balance a stack as you move? or mass/weight changing how the rocks behave? Really nerd it up.
After getting stuck on the deer level, I wondered if I could use the environment to help prop up the rocks, but at the moment the levels are only flat. it probably goes against the art of rock-stacking though, but i thought mechanically it might have been something to play off of. Then I tried it by stacking the rocks to the edge of the screen and it worked like a charm.
I do think there is a lot of opportunity for further development, as the theme and package are good. You could have something solid after lots of polish.