Success!
IF you bought the game off Steam as I did, you will need to:
1) Browse to your game folder and find the folder 'redist'.
I found mine here :C:\Program Files\Steam\steamapps\common\il-2 sturmovik cliffs of dover\redist
2) Try running the Direct X installer. ( This was the problem for me, but I had tried running other installers in there too).
So, It works....not perfect, but I am prepared to wait.