I have just had the weirdest thing happen, despite being a regular and long term DS user.  DS crashed, which often happens when I go to print or export.  So I had to re-open DS.  When it loaded up the appearance had completely changed, fonts had been lost, personal settings gone.  It was like someone had stolen in when I wasn't looking and just jumbled everything up!  I tried restarting my Mac just in case, but no, the jumble looks permanent.

Has anyone else had this happen?