Any I missing something? New build wipes previous saves?

I decided to do a patch update because I was in the middle of playing PP and on the secure mission for NJ the last critter was in a wall so i couldn’t kill it. now as my c:/ drive is too small i install everything on D. This patch not only decided to install on but C:/ all of the progress i made playing the game is gone. i’m hoping the saves on d: haven’t been blown away. If so, my question is, what developer thinks it’s a good idea to make people start playing a game from scratch with each build?!? or doesn’t install in the same directories as the previous version?
Who can I talk to about solving this? I do not want to invest another 30 odd hours to get back to the same point i was! Any suggestions?