Hi Lauren!
For the proof, please just look through and make sure it's all good. You can be as thorough as you want—in a perfect world, it would be a close review, but at this point, it's up to you. I would check the following:
- the pages are in the right order
- the images are all present
- there aren't any formatting issues (like, did an image or text box slip out of place)
- all ll the titles and names spelled correctly
- in the interview, all the speaker initials are attributed to the right passages
and other things like that. Spend a couple hours on this.
The main point of this approval is that the printer receives acknowledgement that you approve what they are printing, and if sometime later down the line, you get the book and there's an error (like they printed page 7 where page 6 should be...), you can't ask them to do a reprint, because they sent you a PDF where page 7 is where page 6 should be, and you said it was approved.
For the press check, this is entirely optional. It would make more sense for one of us to be there to ensure the print quality is as expected, but we've chosen one of the best printers in the world, so I hope that we can trust them. So, if you can't make it, it's fine.
I hope this makes sense and answered your questions :)