On the double tap prompt screen, double tapping doesn't do anything. Also, while I was trying tapping on different areas of the screen, somehow it ended up looking like this:
Thanks! I'm really excited to get back to working on this. I'll have some information on this soon! Saki has gotten back into continuing work on the rewards system as well.
Just so you know, it looks like double tapping to check an answer does work during the actual puzzles, it seems like it's just the tutorial where it doesn't work.