I'm thinking of fitting the idea behind Ghostwalk into a region of my homebrew setting, to get a feel for it. I'm planning on keeping the Ghost effect limited to a specific region (not strictly limited, but the DC to manifest as a ghost gets harder as you get further away from this region). That way I can see how the game plays out with the PCs jumping between coporeal and incorporeal states.
Has anyone run campigns using Ghostwalk? Any comments or advice?