Hi Richard,
New historical tables were added to Bank Rec in GP 2016. So, the process on how the checkbook register prints was redesigned and loads a temp table, and loads all checkbooks, so can take a long time now.
You are correct it does print faster from Checkbook Inquiry. The more checkbook ID's, and the larger the CM tables are, will make it take longer, but will eventually finish.
Seems like Performance is better if some data has been moved to history. The new CM20200/CM20300 tables should not be empty. (Tools | Routines | Financial | Reconciled Transaction Maintenance.)
Many users have also switched to using a Smartlist instead. But if using the Checkbook INQUIRY window, it will go faster too.
If using the REPORTS menu, we just have to wait as it is working by design now.
Hope the information provided is helpful!
Kind Regards,
Roderick