Hey!
I've finished your level and attached a solution replay.
While the solution is fine, I would say you could improve a few things on the presentation side of things. I've attached a "revised" version of the level (+ replay) where I smoothen things out a bit and added some decoration.
For example I was careful here to put the more rectangular blocks and pillars together in such a way that there is no overhang between them and they fit nicely together. Out of the rough stone pieces I tried to make a nice formation.
I also placed the water at the bottom of the map while reaching the edges to the left and right to create a natural pit effect.
Furthermore I reduced the Lemming count a bit and removed the timer, but that's secondary for now.
Maybe you can get a few ideas for your pack out of this revised version.