I had one page that asked for surname but I would have needed to go to the previous page to find it and it wouldn't let me.
Also a few times I needed to enlarge more than it allows me to to see better.
Good concerns. If you get the first names on a sheet continued from the previous sheet, you can skip them and mark that nothing is wrong.
For the Zoom issue, submit Feedback on the link on the left on this page: https://www.familysearch.org/getinvolved/1950
Thank you so much for all of your work.