Your port forwarding is definitely correct -- thanks for sharing the screenshot. And if you were advertsing your server and they still couldn't connect, that means there's no way your public IP was wrong. That's good news!
Now we're getting down to closer to where the issue might lie. Really there are only three possibilities left at this point:
1. You still have a software firewall running in some capacity that you may not be aware of.
2. Your ISP is doing filtering on nonstandard ports.
3. Your router itself is doing "application level filtering" and choosing to block the content, or is otherwise firewalling it off in some manner. There are so many different firewall settings on the various routers that it could be a variety of things with this.
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It sounds like you've already pretty much exhausted issue #1.
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For #2, if that's the problem then you probably need to host the game on a different port. In your server, you can go into settings and change the port to something like 80 -- or even better yet 443, the SSL port -- and then save and exit the server. Then restart the server from the main game, and it should say you are now hosting on that port.
Then you'd need to update your port forwarding to forward that port rather than 32322, and then your friends would have to do one of two things: a) change their port to whatever you set, in their own settings on their clients; or b) connect to you through the advertised public server listing, which handles the port-setting for them based on your advertisement.
The idea with this approach is that some ISPs (mainly in Europe) block whole ranges of ports from having any traffic go through them. I'm not quite sure why, but I have seen it before with our game AI War. A handy way to fool that with any game that supports it is simply to change your game to use one of the standard ports. The reason we don't start the game preconfigured to use one of those ports is that the problem is really quite rare, and meanwhile those standard ports are often in use by other programs that the player might be running (personal web servers, etc).
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For the third problem, it pretty much comes down to poking around in your router settings for anything that says something like "firewall" or "application filtering" or similar. And then making sure that anything suspicious there is turned off. I wish I could give you more specific notes on this one, but it really varies so much by hardware.
Lastly, if nothing of this sort is working, you can always skip all that and use something like Hamachi or Comodo or one of the other free virtal private network providers. These come at some performance cost to your networking, but with the benefit of utter simplicity in most cases.
Hope that helps!
