I successfully transferred all profiles, but pictures not only transfer some of them about 1100 after which the process stops without receiving any error message, I nearly 2,000 photos on the old site.

I have only one message to admin: profiles:

All profiles were transferred (10,687 items)
photos: Profile Photos is now Transferred
You should have appointed your email in the cron job settings. So, if the error happens it will be sent to your email. Please try again with this and let us know.

Also, I would suggest to do a search in Unity Forums for the resolution. Probably, the problem was raised before.
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