I’ve never used Avira Antivir Internet Security, but I think I remember that when I used to use their AV they called their real-time scanner the Guard. I believe that is probably what you are talking about.
Can you please let me know which program you’re talking about? Also, a link or screenshot would be nice?
Yes, Comodo’s HIPS will prevent any program from running or changing any other applications. Essentially even if a piece of malware is not yet detected by any AV CIS will prevent it from making any changes to your system unless you allow it.
Of course for safe applications Comodo will check the file out and decide if it is malicious or not. If it is safe it will be added to the safe list and you will never receive another popup for it.
Avira’s guard only scans for files that it knows are dangerous or that are detected with its heuristics.