Saving Components from a Comparison and misc. questions

[Gnosos]

I'm a brand new user of FreeFileSync, so please forgive me if I'm asking about the obvious.

I have a new MacBook, and I'm trying to migrate files from two dying iMacs to the new computer. To do this, I'm working on my first Update Synchronization, which I hope will migrate only the newer files from the iMac to the MacBook.

First I ran a Compare, which found 2,476,358 files and took 14:49:46 to run. So, my first question is, how should I interpret this. Are there 2.5 M files that need to be migrated, or is this just the number of files that were found on the source computer?

Second, because this was so time consuming, I'd like to save the findings of the comparison, so that should I screw up setting filters, I can just start over. Can this be done? How?

Third, I ran the compare overnight, and it found several errors. Typically it had an absolute path to a file with an error message such as "file not found." How is this possible? Is this just an orphaned link to an inode? Should I have run Disk Utility's First Aid on the iMac before running the compare?

Fourth, and related to the third, at some point, when FFS detected an error, I just selected "Ignore All." Then, after the job finished, there a list of errors appeared. I didn't expect this, but I'm thankful for it. Is this documented somewhere? I'd be interested in documentation on Ignoring an individual error and ignoring all.

Fifth, and related to the fourth, now that I have this error list, can I save it to a file? It would be very helpful to identify potentially missing files.

Sixth, the Mirror Synchronization tutorial video, shows saving a Configuration file. But it saves the file after the synchronization is finished. Since I'm dealing with an entire user directory on the source computer, I will be filtering out many things (e.g., Library and Downloads), which should not be migrated. I'd like to save these filters as I go along, the same way one backs up copies of Word documents before the final version is ready. Can one do this: updating the configuration file as one goes along?

Thanks.

[xCSxXenon]

1) Probably, depends where you got that number.
2) No
3) Most likely permission related
4) Saved in the logs
5) See 4
6) You can keep updating and saving your sync settings

I do question why you have some many files though, what location are you trying to sync?

[Gnosos]

I'm trying to sync my home directory, ~/, which contains most of my life's work: videos, web sites, programs, statistical analyses, papers, etc.