We got bunch of unpaid invoices. When post one payment for several invoices, system automatically posting to wrong invoices and I have to go back and uncheck them all

You will need to turn off “Automatically apply bill payments” feature in new QuickBooks.
To do this task:
From the homepage screen,

  • Select the Company “Gear” (upper-right-corner)
  • Select Company Settings under Settings heading
  • Select “Advanced” under Settings
  • Select “Automation” under Advanced heading
  • Select and turn off “Automatically apply bill payments” feature. See attached screenshot photo for reference.
  • Save
automation automatically apply bill payments feature off
automation automatically apply bill payments feature off

How to print a deposit slip and deposit summary in new QuickBooks Online (QBO)?

In order to print, from the homepage screen

  • Select create (+) sign
  • Select “Bank Deposit” “under “Other” heading
  • Go to small clock icon on top left corner and select “Recent Deposits” slip and summary you want to print
  • Select Print at the bottom middle
  • Select “Print Deposit Slip and Summary” or “Print Deposit Summary Only”
  • Select “Setup and Alignment” feature in order to test

Note: In order to print “Printable Deposit Slips”, you will need to purchase special printed form from Intuit, which is not cheap. Print alignment feature is not available (or do not work) at this time.

Print deposit slip
Print deposit slip

New QuickBooks Online (QBO) – Print Checks help video