I saw what you guys mean by lock-up. I think it happens when too many combos stack and you try to select a jewel. For now all I can advice you to do is to wait for the falling animation to get completed then try moving other jewels.
I will be looking up on that lock tommorow when I get to my office. Sorry for any inconvinience caused.
Thanks for the feedback. There is actually some music playing in the background. I suggest you turn up your volume up. If you still think the forest sounds aren't enough I can consider adding a light ambient sound with it.