iCloud Sync "Import of file failed" DT3

I took a large (5 Gb) DT3 database, set up iCloud syncing, and was able to successfully sync it to iCloud.

I then tried to sync the database to another computer using iCloud. The sync worked partially but a number of file import errors occurred. Why might that be?

Hold the Option key and choose Help > Report bug to start a support ticket.
Thanks.