TrakStat plugin - loss of data

I've been using TrakStat with my Transporter for a number of years and it works really well.
Previously I had my music database on a USB2 external HDD. However I have switched to a WD My Cloud NAS drive. I copied my music database over to the new My Cloud NAS, but I seem to have lost all my TrakStat data.
Where would the file containing the data be?