An alpha version had the save button working with just a click, but after getting some feedback, I thought keeping it pressed might be a better way to avoid accidentally overwriting patterns. So you need to keep it pressed until it stops blinking now. It is explained in the tutorial, but I can see that it might be counter-intuitive with how the rest of the buttons work. I'll see if I find a better solution for future versions! Probably also using the display to the the left to indicate that saving worked (or failed).
I'm glad you love it and thanks for the feedback! :)