Decided to post it here. Cause this game is so great the Downloaded version (aka https://redball17levels.weebly.com/red-ball-5.html version) and the kizi version have their levels swapped. I have taken my own free time and figured out which levels are which.

The format is it (Download level number) (corresponding Kizi level) 1, 1 2, 2 3, 3 4, 8 5, 10 6, 9 7, 4 8, 6 9, 5 10, 7 11, 18 12, 19 13, 11 14, 12 15, 13 16, 14 17, 15 18, 16 19, 17 20, 20 21, 27 22, 28 23, 30 24, 21 25, 22 26, 23 27, 24 28, 29 29, 25 30, 26

Thank you for reading and I hope this helps :)

But IL order is Kizi based, right?

Yes, IL order is the Kizi order

I think this list (and the second being the other way around) should be in a Guide for RB5