Probably the SPC you tried is so old that it used a pure Addmusic, that is, an Addmusic with no MORE.bin inserted, so techinically it will be a SMW track, not a Addmusic track, so my tool won't block them. I assume that's not a problem I guess since these type of ports are rare and obviously ancient enough to people don't care anymore.
About the crashes I will see, the "play analysis" one should be because of the semi-unstable player the tool uses while the second one should be simple enough to fix. Either way, they're not major at least.
By the way, if anyone find a rather poor conversion and you think it's possible to make the tool process it better (that is, the song don't use insane methods like changing envelope 500 times per note or full of legato), feel free to link it here and I will take a look when possible and/or give possible workarounds.
Oh and thanks for the comments. This tool was pretty hard to code and I'm happy that most people liked them. Honestly I thought half of the community would hate me for releasing such tool but apparently I'm wrong (I hope).
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