The OLE alerts (and many other aspects of Application Behavior Analysis - ABA) result from the way that applications communicate “behind the scenes.” You can see these alerts even after one of the applications has been closed. This type of behavior can be utilized by malware to gain internet access; thus CFP monitors it and alerts anytime it detects such activity. The downside, CFP doesn’t know what is good and what is bad, only that it’s happening.
The general rule, as given by Comodo, is that if you know the applications involved, it is safe to Allow. If you Allow with Remember, you shouldn’t see the alert again for that combination of apps. A single Allow will be for that session only, as will a single Deny. Add Remember to the mix, and you create a rule either way.
With your Skype/Outlook scenario, if you go to Security/Advanced/Miscellaneous, and check the box, “Do not show alerts for applications certified by Comodo” then go to Security/Tasks/Scan for Known Applications; follow the prompts and reboot when finished. This should pretty much eliminate those popups for you (they should both be on the safelist).
For svchost.exe, you’re generally safe to allow with remember so that you’re not bothered by it. After you do what I just instructed above, you shouldn’t see svchost.exe alerts any more either, though. For what you “need” to allow svchost on… it’s pretty much guaranteed that you need it for DNS queries (Outbound, destination port 53), DHCP lease (Outbound, destination port 67; inbound, destination port 68), and also for using Windows Automatic Updates (not sure the protocols there, as I don’t use MS auto updates).
For the emule scenario, you probably got one of the ABA alerts, as discussed above. Thus when you deny, CFP deems that you must have malware trying to get out using FF, so it blocks FF as well. If you clicked Remember when you denied it, then that will set rules in place. I’d remove both application rules in that scenario, and reboot. If you ever deny an app in that scenario, CFP will block the application it’s using to access (such as your browser or email client). If you don’t “Remember” and deny, since it will be for that session only, generally closing and reopening the application will do the trick; otherwise a reboot will.
Hope that helps,