A few years ago when I used Comodo with the much more restrictive HIPS "Paranoid mode", the
only way I could manage to make this mode usable without crippling Windows was to immediately put it in "Learning mode", then reboot several times, log out and back in, do most of the basic stuff I would normally do on a daily basis such as open the web browser, email client, any office apps, and most of the basic Windows actions such as open Explorer, check updates, settings, etc...This way rules would be automatically created on the fly.
It's not ideal, of course, but there was no other way otherwise it would bork Windows because the HIPS would block something critical that Windows needs to function properly. it seems the same issue, maybe to a lesser extent but an issue nonetheless, occurs with HIPS in Proactive mode. Obviously Learning mode must be done on a known, clean system, and the user must take care not to incur infection while doing so
EDIT
Perhaps Comodo devs could consider baking into the product, a minimum set of rules that allows Windows to function at a basic level whenever the user wants enable HIPS in any mode.