So, arc_conv is still giving me fits. No punctuation works, and apparently it doesn't like when I copy and paste something. No biggy, it's annoying but I can work around both of those. But trying to figure out what is causing issues, I edit 1 line at a time:
Line 1: no punctuation, but displays correctly and doesn't break anything.
Line 2: character name replacement - again, doesn't like punctuation and has very short length limit, but again, worked around.
Line 3: makes first two lines display incorrectly and game crashes.
Increasingly looking like I'm probably just going to do this for myself as a script translation (ie, not screwing around with trying to re-import things into the scenario.arc)
I tried again with mjarc, and now I can't even figure out how I got it to re-import last time. It just keeps the original Japanese, no matter what I do.