Hey so I guess itch doesn't like my message with a lot of words and images so I put it on a doc for you to read: https://docs.google.com/document/d/10DHiLrcP-SeeHw-p2tggL4Jk7eU_LtW-mbRkl4BZST4/...
Awesome! You clearly put a lot of effort into your reply.
You understand most of the tools and were even able to make the entire 9x9 area look like the 3x3 area on the left. But you already knew that this can't be how you solve the 4x4 level. And in the future I might change the first level's target to not be square. It may be a 2x3 or 4x3 rectangle. Would that help you figure out how to solve a level? In fact some of the later levels are already rectangular, so making the entire area look like that can't be right, right? :)
I try not to spoil the solution, because I think you're super close to solving the first few levels all by yourself. The third level is a little difficult, but you can skip that and maybe solve the fourth.
Learning how the game works is supposed to be part of the puzzle and you're doing quite well. It's unfortunate that you got stuck this close to solving a level. I had hoped that discovering the game mechanics would feel rewarding, not frustrating. But I don't have much game design experience (I'm more of a programmer than a designer), so I might need a few more iterations before the game is unambiguous, less frustrating, and maybe a little fun. :)
Maybe put a hints/help feature that guides player to try out the tools (whether you want the feature to spill all info or not, it keeps players on the game and pushes them to try each tool without feeling completely lost). So frustrated players can have more relief. And I've noticed that this feature has the opposite effect on less frustrated players, by motivating them to go like "oh, I dont want to use a lot of help, I can do this on my own" (If you want the feature to give hints for each level solution too...)