It's good, but it can be great
I thought this could have been a great game, until the point where the order of which things to come is also an issue for no reason.
At level 4 or something you need to make 4 while you are an 8. You have a 6, a 5 and a 3. you've got one plus and two minuses. I wanted to do: 8+5-3-6=4. The game wouldn't let me for some reason because it's coded so that even though there are multiple solutions of wich the order is in, the game only lets you have one order. That is annoying because this makes you unable to think you want yourself, but how YOU, the creator of the game, set it up to be. even though your solution might be more easy to get, I like to make the solutions in my order. It is annoying that the game does not let that, and you just die because of it and have to restart.
If you can make sure that the order of which the equation is solved isn't restricted to just one option, I would love to play it again! Keep it up and make more stuff like this!