[for payment] Teach me how to deploy in bulk multilple raspberry os

Hi, I need to write on microsd (32gb)every year dozens or hundreds of new .img files with inside the Raspberry OS and I need to control them remotely trough remote.it . Please teach me how to configure these .img files in the way that I can install remote.it automatically at every start of the OS.
Here the manual https://support.remote.it/hc/en-us/categories/360000746111-Mass-Production-Preparation
Ps. there are 2 methods to do it: Auto and Bulk Registration. I want to use the Auto Registration, not the Bulk Registration.
We can do tests also on smaller microsd (8 or 16gb) if needed to do some tests.

Hi,

Did you follow the instructions for Auto Registration?

Are you having a problem? Let me know what you did and where you got stuck.