I did the test a while ago and I didn’t care that much, but now that I think about it again, I believe it might matter.
The test was done on ShieldsUp: http://www.grc.com/intro.htm
so as long as my router firewall was activated, all ports were invisible
but as soon as I deactivated it, and kept CFP active, many ports appeared in the test as “closed”, and of course visible.
Do I have to consider that those shown ports were my router’s ports or my computer/Windows’ ports? Of course the only detected IP was my router’s IP, so the test might not be relevant for CFP. A confirmation would be appreciated, thanks.