For people customizing CCleaner via winapp2.ini who have had CCleaner crash this is a possibility that I stumbled upon today purely by accident.
You add a program to winapp2.ini that has the parameters inputted incorrect, example:
[RAV AntiVirus Online Virus Scan (Log)]
LangSecRef=3024
DetectFile=%windir%\Downloaded Program Files\rave\avirexe.vdm
Default=True
FileKey1=%windir%\Downloaded Program Files\update.log
Notice that FileKey1= is using an incorrect path variable "\" that CCleaner doesn't support for files, this will resort into a crash dialog when running Analyze, or Run Cleaner:
This is the correction:
[RAV AntiVirus Online Virus Scan (Log)]
LangSecRef=3024
DetectFile=%windir%\Downloaded Program Files\rave\avirexe.vdm
Default=True
FileKey1=%windir%\Downloaded Program Files|update.log
Notice that FileKey1= is using the correct variable "|" that CCleaner supports.