When you say not routed correctly, what exactly does that mean? I'm having similar problems after just replacing a lift pump and there's a pretty good chance I did something dumb - but I thought I did it all by the book, which means I wouldn't be able to identify what it was without some outside help.
-N
I had two fuel return line outlets plumbed together after replacing the IP and injectors. Obviously, that does not work when trying to send the extra fuel back to the tank, hence the start, run and die syndrome. If you are a little more specific with your symptoms, maybe some pics of what your line routing looks like currently, someone on here should be able to diagnose it. I was trying to avoid putting that first line of this post out for everyone to see, but if it helps someone else, then I can handle the shame!