I ran into a bug in the butterfly and scythe stages, the moment I entered I won and advanced. After the scythe stage the game hung in the player won screen.
Thank you very much for your comment, there was indeed an error, I corrected it. In the EASY mode, unfortunately, there were not 10 but 0 opponents to defeat on these two tracks. But you wouldn't have faced this if you chose HARD mode. :) Thanks for it, your sign meant a lot!