Interesting, I would think a shorter name would work better, since the name is the seed randomizer. I'm not sure why the achievements don't work on Wavedash... some of them do, and some don't, and for the life of me I can't tell which ones work without actively trying to get them all (there's 40!).
And I was hoping to add some control indicators in-game, but ran out of time. I will certainly be adding them as soon as I get a chance. The notes in free Music Mode are probably the most difficult... it's S, A, D, W, down, left, right, up, or on controller down, left, right, up, A, X, B, Y in order from the root note to the octave. Triggers change key, bumpers change tempo. I hope that helps!