I happened to run across this thread while googling, you've posted in the wrong spot.
http://www.codeplex.com/DotRas is where you should have posted your question. This discussion forum is for the CodePlex website.
Now, to answer your questions:
Yes, DotRas can be used in a C++ 2008 project however you must use a "CLR" project type. I don't know if you can use .NET from the others (you probably can if you host the framework yourself, but I'm not going to get into that).
No, you do not need to do anything to the other machine for DotRas to work successfully. As long as it has the appropriate permissions to run, it will work perfectly fine.
If you have any other questions, please make sure you post in the correct discussion forum so your question gets answered in a timely manner.