I have found this strange thing happen to me and my friend,
When i right click and select properties on the comodo firewall 2/3 installer, the entire system will lockup and hang for a few seconds
this might be a bug in the executable unpacker used on this installer.
If it is the major problem… :
Maybe it is just an intensive use of the CPU. Does the installation process continue after that without error?
Yes it seems to be just a hang while avast is scanning it… 
So… don’t worry. Anyway, thanks for reporting.
Something strange just happend while testing all the assortments of bugs in comodo firewall 3 i saw that after a hang happen comodo firewall 3 puts the installer in my pending files (basicly meaning its changed) but after i removed comodo firewall 3 for reinstalling to test something else the installation crashed.
redownloading the installation fixed it but that means that either avast or comodo firewall 3 (or both from another conflict between them) corrupted the installer, i wonder if this reproducable…
i also got the hang on a winrar sfx (a self-extracting archive a exe that extracts it self).