Hey Wolf!
Thank you very much for your kind words and for taking some time to play my game! To be honest, I was not expecting anyone to play it and I was very surprised to see that you even recorded a video about it!
To answer one of your questions, the Music and SFX were not generated by AI, just the sprites and some lines of code.
In the last level there is a platform close to the Red Flag where you can go up one more level and proceed to collect the remaining coins - there is a video walkthrough attached in this page that you can check if you would like!