I just downloaded version 2.3.219500.176. Everything seemed normal when I went to use it.
As expected, the program wanted to reboot the PC to check for root kits. Very early in the boot process I got the ugly BSOD. IO SYSTEM VERIFICATION ERROR IN HIDCLASS.SYS (WDM DRIVER ERROR 22E) [HIDCLASS.SYS+1902 AT B90E2902].
This PC is a Dell Optiplex GX260 with 2GB RAM running Windows XP Professional SP3. I am an administrator on this system.
One thing different about this system is that it uses an Ultra 4 port USB KVM switch. It could be possible that this program does not like this KVM switch.
I was able to turn the PC off and connect a PS/2 keyboard. Selecting Last Known Good got me up and running again. Comodo Cleaning Essentials resumed its scan after I logged into the PC. It just skipped the root kit check.
I am not discouraged as I see this as being a very useful tool.