Just run procmon to see what the certfix does... I can see it puts em.exe (eset command line scanner) in a %temp% folder..... I copied that file and the dat file.
Comparing the em.exe with the one in the eset file security folder (ecls.exe) i can see the command line scanner version is from 5.0... The version in the program files folder is 6.5.... So i can believe the reason why this fix craches on 6.5 versions of eset