Aye, the C++ page is a good place.
As to why C++ over C:
Personally I prefer C. I really do, that's what I first learned and that's how I think. That said, there are some things which just work better using classes because it integrates the data structure with how it's implemented.
Math vectors are a good example of this. Vectors in C and Vecors done using classes really show the power of C++ over C for many things.
That said, I've done my best to keep the code fairly clean and weird C++ operator free. For what I've coded anyway. I've had some more C++ savvy programmers work on some things and they tend to like more complex things that boggle my mind.
I can upload my MSVC project files, but I think they're path specific. That is, they might only work if your source code is set up the same way mine is, in the same place on your C: drive.
As to the GUI: I am presently finishing it up. Presently there are some controls but they aren't integrated into the engine yet. So you can slide the slider and click the button but nothing happens.
If you would like to join, great! I absolutely hate how long it takes to finish up a project like this. Feel free to message me on AIM or MSN later today if you would like a more real time discussion.