The problem was the Options.txt file had been changed to Options.bbx and so when opening the file the EFILive software attempted to interpret the file as *.bbx info from what was really a *.ini options file. The code for reading a *.bbx file expects a 4 byte integer in the first four bytes of the *.bbx file (the number of sub-files contained in the bbx file). That value was obviously huge "1595940923" and caused an integer overflow.
The software now takes extra precautions when loading *.bbx files to validate the values being loaded more carefully.
Regards
Paul