The tutorial gets stuck at:
When buying a polyomino you can move it with the arrows, or click the place the most left of the polyomino needs to go. You can also rotate the polyomino with the button i highlighted with red and flip it with the button i highlighted with blue. Try it out for yourself, buy the middle polyomino and placing the attack in the green square.
After placing the polyomino, you can't do anything to continue the tutorial. Any button says "please take the action specified in the tutorial" or something like that.
Also, when you described something, there should be an action associated, rather than having to continue first and take the action in a second tutorial step. Better to have the 2 combined.