I'm using the Lyric Diphonizer 1.1 by 564. I am seeing that there are a lot of weird names, like e d, so that actually might be the problem. Here's a screensot of the UST. It's the crescent moon part of the "my favorite Vocaloid songs EXTEND" UST group.
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[doublepost=1543684932][/doublepost]I think I fixed the issue. Once I noticed that there were those odd notes, I tried to delete them and then convert it. Those notes were definitely the problem. Thanks to everyone Who helped!