Yeah I was afraid of that, but I guess that just means it's time for more detective work.
Thanks for the response, and it does help to know if I see the UTF-8 error again that it'll likely resolve itself!
I don't know if this information will help at all, but I was also having trouble trying to get a DVNO mod to update automatically. It failed with an IO Exception error, but installed manually as a .pmp just fine.
I spent a fair bit trying to check if it was something with Windows or my browser...