I have one bit of constructive criticism for you. Every single Major/Minor scale should have exactly one each of ABCDEFG, so that written music makes sense — each line/space corresponds to a "letter", and the key signature tells you how sharp/flat that "letter" is. The tool gets this wrong for example in C# major, where you should have the 3rd step be E# instead of F, and the 7th step to be B# instead of C. A particularly pathological case is D# major, where almost all notes are misnamed — You should have D# E#, F##, G# A# B# C##.

Hi, yes, that's a known issue. I added flat/sharp button as an option, but, I think that makes things even worse. I am working on a fix for this...