I was having trouble installing programs, i.e., nHancer. Installation would stall showing 99% usage with cvtres.exe in the Task Manager. I thought it was nHancer, so I changed Nvidia drivers and nHancer versions. No luck. I also had problems with installing upgrades with Net Framework. I decided to make changes by starting with un-installing Comodo Memory Firewall. I rebooted and all problems went away. No problem installing NHancer, Net Framework or any other programs. No Task Manager usage showing for cvtres.exe anymore.
If you are only using CFP and getting high usage with cvtres.exe then it may be “SafeSurf” that was provided in the recent versions. SafeSurf provides similar protection like the Memory Firewall, so maybe it has these problems also.
Just passing on info that worked for me.