Unable to restore a large file tree

I’m running Comodo on Windows 10. I was moving a big tree of files
from an old to a new laptop. It’s a big tree of files, rooted at my custom
folder C:\apk
The C:\apk tree also includes my Thunderbird profile:
I said to Backup Files and Directories, then
selected the C:\apk folder
Selected CBU Format
Full backup
I selected the target folder for the resulting file.
After Comodo got done, the resulting CBU file was just over 1.4GB, about what
I expected from all the files (over 2GB uncompressed).
I copied the file to the new W10 system, then ran Comodo and restored
everything by checking all the boxes.
However, when it got done, it seemed to restore only the path to my
Thunderbird profile (tho I’m not sure it restored everything). It restored
various top level (under c:\apk) folder names, but the folders were empty, no files nor subfolders.
I even tried to specify certain files but Comodo would not restore them.
When I ran Comodo to restore those chosen files, the display would show it
restoring the Thunderbird file tree instead. In other words, it seemed
to restore only files in the Thunderbird profile tree no matter what
I asked for.
I finally did the file move using robocopy so it’s done, but I don’t
feel like I can rely on Comodo as a backup solution until I find out
the cause of the problem, although I really like the tool.
I did a chat with one of your tech support people, and she suggested
specifying ‘Email accounts’, but that looks like it allows you to back
up Thunderbird without having to know where the profile files are, but
I already know where they are.
Is there anything I can look at to figure out why the other files
won’t restore? I still have the CBU file if you have any suggestions
I can still try them.