I updated to 13.19 and it prevented Big Box from launching at all. I could get it to randomly work 1 maybe 2 times if I rebooted big box (not the machine) about 20 times.
The only fix was to delete the "core" folder, delete the big box and launchbox exe files in the main folder, then run the 13.18 installer to revert to the older version. It was then, and only then, that I was able to get big box to work 100% of the time.
I tried a new install folder completely and had the same issue. This leads me to believe that the update itself is broken or fails to install a required piece.