UBB.threads PHP Forum Software Community Forums UBB.threads 6 Version 6 Support Import completes, but nothing has imported?

Hi
Trying to import data from phpBB.
My files are in the correct yaml format. The import process seems to run okay, reporting its progress. When it completes I log back into my BB but nothing is there. No users, no forums nothing.

Does the import create a log file of what its doing, and where import errors are written??

Thanks