I was just talking about this the other day with glowing nostalgia. What a delightful unexpected event. I had a similar experience to you with the flash version and it lead me to start making music myself and get involved in a scene that really was one of the most valuable experiences of my young life. Having the graph to explore the lexicon for what exists and examples side by side to get an understanding of why felt like finding a secret treasure map. I can only think of one other flash program I've gone and searched out in the years since and it's the dumb Something Awful Jeff K cartoon making fun of Linux users [0]. Any time I've shown the old version to people over the years it blew their minds. If I ever make anything half as impactful I'll consider myself pretty lucky.

[0] https://www.somethingawful.com/feature-articles/jeff-ks-user...