Thanks for posting this here in the Community, @TWBC . 

Unfortunately, I do not have contact information for Dataswitcher, but I will offer what support I can to try and get things back on track.

First, do you have the ability to re-run the conversion? If so, we can make sure that you complete the pre-conversion for Sage 50 to lessen the chances of any errors. Link:  https://support.dataswitcher.com/support/solutions/articles/43000283610-pre-conversion-checklist-sag...

I also found that Dataswitcher only works with Sage versions 16 and up. Is your Sage version 16 or higher, just to be sure?

Additional details about this is highly appreciated. We'll do all we can to help. Keep safe!