I’ve read that: “Recognize when a program is listening on a certain port”, and then allow incoming connection on that port automaticly, is removed in v 2.4 ?
Why is that?
If I want to run a server, what do I have to do?
Is it correct to create a “network monitor” rule, allowing to allow any incoming connection on fx port 80 ?
Or is this unsecure?
Yes, you will need to make a network monitor rule to allow inbound access to your web server. Without adding this rule, all unsolicited inbound requests are blocked by default. This has been the case in all versions of CFP V2.
The “Recognize when a program is listening on a certain port, and then allow incoming connection on that port automaticly” you are referring to is, I believe, a loose description of CFP’s adaptive stealthing. CFP will, by default, stealth all ports unless there is an active application using that port. If there is no active app, then the port is stealthed.
With a “port 80 - allow” rule in place, users will be able to contact your web server (assuming you’ve forwarded the port if you’re behind a router). Not just the good guys, but the bad guys as well. You’ll need to make sure your server is properly configured, patched and locked down before exposing it to the web.
Hope this helps,
Ewen 
Ok, so my configuration of comodo is correct?
In fact I only need to select incoming connection, but otherwise?
A strange thing I found out today.
Normally, I am behind a router (forwarding ports to my pc),
and I could not access the webserver unless I created this rule.
Today I am not behind a router, and even if I do not set up that rule, I can connect to my server from outside, using the external IP. How can that be?
Secondly:
Is it correct that only the programs that are allowed internet access in the application monitor, will be able to use this open port?
Last:
Would it be wrong just to make a rule allowing all ports? (TCP/UDP)
You say that if no apps. are using the ports, all of them are stealth ?
Other firewalls opens the port when you accept incoming connection to the server once.
Creating this rule in comodo would make comodo act the same way?
Is that a bad idea?