I too have had this same problem. I had 8 years worth of pds files that mysteriously dissappeared when I upgraded to PD14.
Unfortunately I didn't notice this until over 30 days after the upgrade so that my Carbonite back no longer had the pds files.
Can someone explain why PD14 deletes the previous version pds files? It doesn't make any sense.
BTW, The upgrade did not delete the files immediately. I checked after the upgrade and all my files were intact. I even did some edits with the older pds files and produced some final videos. Some time after the upgrade the files disappeared. Also, it only deleted pds files in the same directory. Any chance that these pds files were archived by PD14 using some other extension or name?
If not all my work is lost! I quess I should have had a better backup procedure. Still, it doesn't make sense that PD14 would do this.
Since I've lost almost all my investment in time to this product maybe its time to look at a different video editor.
-StokeDog