I use several registry cleaners because not a single one finds it all.
One of those I have found is AML Free Registry Cleaner, currently v4.13. That one is the first registry cleaner I see finding a total of (in this case) 840 HKLM\Software\Comodo\Firewall Pro.… so called invalid keys.
Going over the list, not a single one is invalid on this computer: rules with a *, or rules with files not existing at the moment of the scan…
First time I used it some weeks ago, it was nice finding indeed invalid and obsolete rules from e.g. Defense+ in a batch and noticed 99% was mistaken. Cleaned those up but no new real invalids. Been looking for a tool that offers a view on ‘invalid’ keys from the CIS package.