Hi vanda,
From what i know warp drive does not create gravity but alters it to their advantage

.I don't how these kind of machines could do this but i've read that they use both negative and positive energy to amplify gravity waves which in turn warp spacetime.Also to create the warp bubble to protect the space ship.
Your centrifugal force idea is great but can't we just make artificial gravity 1G. How does the ISS make 1G?
One problem that i have found is that it will compress anything in front of the space craft and expand anything behind thus destroying everything In its path.
Unless we can make a clear highway.

.Which is virtually imposible with our technology now.
It might just be posible one day.''If we do not destroy ourselfs we will one day venture to the STARS" [Carl Sagan]
orestis