Hi anon441204.
I’m no expert in PTXprint, but I’ve played around with it a bit. You can adjust the copyright info to your liking. If you toggle the advanced settings, at the bottom of the page…
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…then you can go to the ‘Basic’ tab and under copyright, you can type whatever you’d like there.
Sorry I can’t help with the error messages right now. I have often had many error messages, some of which don’t prevent the draft from printing, but some that do.