Well, I've been schooled on why I had problems, and offered another solution, which I have now done:
tip 1: disconnect all external and internal volumes not needed for the migration (i.e. external drives, thumb drives, etc.). You can physically detach external items, and you can use Disk Utility to unmount internal items. If you don't understand how to use Disk Utility, then skip that part.
tip 2: make sure your destination system is a Clean Install and DOES NOT have any user accounts yet.
1) "Transfer Information" option is called "Setup Assistant".
2) If you have multiple user accounts, and you are working with a Clean Install, it's best to import the user accounts one-at-a-time, in order of User ID (it's a number), and only the first account through "Setup Assistant". The rest go through "Migration Assistant" later. To find User IDs, log into your current system, go to SystemPreferences>Users&Groups, unlock the padlock, and Control-Click on each user's name in the left of the window, to get "Advanced Options". DO NOT MAKE ANY CHANGES, but write down each user's "User ID".
3) During your Clean Installation/Setup, use "Setup Assistant" to import ONLY the user account that has User ID "501" (or next lowest if no 501), plus "Applications", "Other Files & Folders", and "Computer and Network Settings" (I did all 3 options). Again, don't do any other users yet. It's best to do those later with "Migration Assistant". Click to start migration.
4) After "Setup Assistant" finishes and your new system finishes starting up, if you want to import additional user accounts, go to Applications>Utilities>MigrationAssistant and run it. Select the next user account in order of User ID again, likely "502" (or next lowest if no 502), and migrate that account only. DO NOT select the "Applications", "Other Files & Folders", and "Computer and Network Settings", as you ALREADY did these. DO NOT select any other users yet. Click to start migration.
5) After "Migration Assistant" finishes, repeat #4 above as needed for additional accounts, still one at a time, and still in order of User ID (503, 504, 505.. etc.).
Conclusion:
I'm working with High Sierra and Mojave aged systems and apps, so please consider my opinion with that in mind.
Using both "Setup Assistant" and "Migration Assistant" as described prevents permissions problems, rather than using one or the other, which could create problems.