As I've just had this problem, I'll add some more information -
First, I've been using RM under CrossOver for almost a year and not had this problem. Have just started up MacBridge and it failed with this problem whilst I wasn't actually accessing RM but these forums. When I went back to RM, it was sitting there with the error. (By "went back to", I use multiple desktops (or Spaces) with RM on one desktop and my browser - Firefox - on another. I 3 finger swipe between the 2 using a Trackpad.)
I'm using Mavericks 10.9.4 (10.9.5 waiting to be installed) on a mid-2008 4GB iMac. (My CrossOver is currently at 13.2.0, but I've used all versions 12.5.0 without any great problem.)
Note that I subsequently ran all the database tools and they were all clean. I was running using copies of my CrossOver/RM folders.
OK, just had the problem again. It definitely occurred whilst I was accessing the forums and with RM sitting there with a Pedigree display panel. Previously I had accessed one of the people in that display and looked at one of their facts, and also brought up the first FSFT panel for a matched person - and probably also looked at the FSFT information for one of the facts in that panel. However, I had returned to the pedigree display before switching to the desktop containing the browser. Switching back to the desktop containing RM and the error pop-up was sitting there (or popped up so quickly that I was unaware that it was only happening at that time).
Both my MacBridge and CrossOver RMs are at 18.104.22.168.