I'm afraid the text below is probably rather difficult to follow, but I've said everything which I think might be of relevance.  I guess some of it will be irrelevant.  Sorry, in advance.

First, I should say that all my records are held on R3, version 3.4.6.  The copy of R6 that I'm using is an ''empty' copy of the latest version 6.15.4 that I'd only just installed. The appropriate add-ons to enable the transfer had been installed.  Also, my copy of R3 has only 1 survey listed, ie the one I was attempting to transfer to R6.  It comprises a subset of 65k records from my main dataset and was being exported for test purposes prior to doing a full export at the end of the year.  Before creating the survey this morning, I had deleted from R3 the names of other surveys that I'd made in the past because I knew from experience that Bulk Move exports the names of all surveys, not just the one selected for export, and these show up in R6, albeit without records - and I didn't want that to happen

My first attempt at transfer froze during the last stage of importing data into R6 from the temporary files generated without mishap.  After 3 hours I aborted via Alt/Ctrl/Del, the R6 abort button being non-functional.  I restored a backup of the original empty database, and repeated the process but with the same result.  However, this time I checked to see whether anything had been imported.  The summary showed 104k records!.  I opened Observations and found 5 surveys listed.  All were surveys I'd created a year or so ago when exporting subsets of data to R2002/6 for passing on to national scheme organisers.  The survey I was attempting to import was not listed.  I checked my C drive for " *.EXP " files (the format used by R3 for import to R6) and found two...... the one that I wanted and one from a previous R3 export some while ago.  I know for sure that I selected the correct exp file earlier today, nevertheless I deleted the unwanted exp file, and repeated the import process to R6.  Same result, though this time I aborted soon after the import froze.  I noticed that the process listed "zip mdb file" as the stage immediately before the "check for duplicates, validate and import", so, wondering in ignorance whether R6 had extracted data from the wrong Recorder Export zip, I searched for other zip files associated with Recorder (I save copies of datasets I've exported to other users) and I cut/pasted them to a memory stick to remove them from the system.  I repeated the import process, and with the same result: the process froze near end but 104k records were again listed in the database summary.  Time to give up.  In case it has any relevance: when I clicked the top survey listed in Observations to see whether it would expand to show survey events, it returned an error message "unauthorised/illegal action" or something similar.  The other 4 surveys, which I clicked previously to the top one, showed no events.

Can anyone make sense of what has gone wrong, and see a way forward, please?