Excellent! I'm glad you're using my changes, I won't have too much time to maintain this.
Two things:
- I have also sound support in my changes but it was commented out. The current executable on my website has it enabled. Not the sources though but it's just a matter of commenting in 3 function defs and a fn call. Pls tell me if you cant' figure it out.
- From your nice snapshots it looks like the transparency could be a little bit more.
I've posted on my website another tkbd.png file which is more transparent. Could you pls give it a try. (I mostly tested on white background, on black it seems a diff story)

Thanks,
Daniel