And that's just how OpenUtau does it. Vocaloid just kinda breaks up words and extends them with - as the way to do it for both. Really just do research on the program you're using to see if it handles things differently or not because it can get confusing.

Of course! The plus thing is somewhat specific to SynthV. Most softwares just have either minus or plus do both depending on the lyric. OpenUtau uses plus for everything but using +* let's you extend a specific syllable

Though I guess that's kind of the no shit thing huh? The only other thing I could tell you is that putting - as a lyric will extend the previous lyric where as entering + as a lyric will break up the syllables.

Not sure if I have any useful tips. I kinda just figured it out as I went so I guess just keep practicing. If there's something you want to do but you're unsure if it's possible, look it up. There's usually a method for whatever it is you want to do.

Gonna be honest I completely forgot about this 😭😭😭
If you want to talk more about this then I'd be happy to! You can add me on discord if you want.

I'm at work right now so It'll be a little bit but I'm happy to discuss this more when I can!