I've been running Timeslips 8 for years, these days on virtual machines.  The tsrtexc.dat file was in the 12 megabyte range for years.  Then it suddenly grew to 64 mg. and then to an unsustainable 1.4 gigabyte.  I deleted the monster file and substitutes a 67 megabyte tsrtexc.dat file that I had from a backup.  Everything seems to run fine but I'm wondering what does the tsrtexc.dat file do.  I noticed that if I erased it entirely, Timeslips 8 still seemed to run.  Any help would be appreciated.  Bob White