To put it bluntly:
You can't put an aircraft engine into a car and expect it to run perfectly. It may work but it'll swallow more fuel than you can ever pay in your lifetime and the driving comfort will be abysmal.
Il-2 1946 is based on an engine that is more than ten years old already. That is prehistoric history in game development terms and most of nowadays technology wasn't even thought of back then. Updating it is not an option since the engine has already been pushed beyond what it could run without jumping through the hoops so any kind of "hi-res" or "2011 gfx" is not going to happen. That, essentially, is what Cliffs of Dover is supposed to be. Once it works fully, that is.
