OK, went through the link that Keets kindly provided but in the end the Checker declared both TCP and UDP to be not open or not reachable.
Not sure where I went wrong, here’s my Broadband setup page:
Any ideas what I did wrong?
Ed,
The problem is, you’re not routing the packets anywhere as the up address you’ve put in, is the ip duress of your router.
What you should be doing is routing any unsolicited traffic to the IP address of the pc your hosting on. You may need to setup a fixed IP address for your pc if your router doesn’t allow your to route to specific MAC addresses. The IP address in your “inbound” should Be the IP address of your pc.
If you still can’t get it to work, download teamviewer and I’ll do it for you remotely.
Much obliged to you, mate, that’s a classic example of the dangers of a ‘little bit of knowledge’ 
Is there an idiot-proof way of determining my PC ip address? I will have a go at it tomorrow afternoon when I have some hours free as I’d like to avoid you having to waste your time if I can do it myself 
Open a command/dos window (accessories->command).
Type ipconfig
Your 192.168.x.x IP address will be displayed.
The thing is, if you’ve got more than one device on your network then you will need to setup a static IP or make sure your PC always gets this IP address.
Sometimes you may want to leave automatic IP assignment, in order to comfortably connect mobile phones, laptops, tablets, etc…
In this case, it’s possible to have the router assigning the PC a fixed IP, linking it to its LAN card’s MAC number: every router has a page for this kind of settings…
Yep, that’s pretty much what I said two posts up. 
Not every router has IP address to MAC address allocation though.
OK, PFP checker says port is open. All hail Keets 
If anyone can help me test in Hyperlobby later on please let me know.
Can anyone enlighten me on Hosting Cliffs? Ports of forward etc. any help much appreciated.
If you can host in old IL2, you don’t need to change anything in your router as you can specify which ports you want to use in game. (Port 21000)
Thanks Keets. I’ll try that. Now I just have to remember how to access my router.
I have found this, can help?
http://airwarfare.com/sow/index.php/beginners-guides/221-quick-a-dirty-guide-for-beginners?showall=&start=9
On monday I discovered that I can no longer host in DCS, but I’m 99% sure it’s due to my new crappy ISP. 
Hmm, why was this showed on latest posts for me? 
Well we are i two with me. It showed me as a recent post as well 