First off, thats a mighty small turbo for that motor...
Are you running someone else's base map? If so get it tuned for your car, every car is different.
Is the oil drain line verticle, or is it angled? The oil can pool up inside the turbo (bearing housing) and leak out when it cant drain fast enough...common problem.
Doibt your rings are toast, you wouldn't hear rattling. Describe this rattle. usually a rattle (from the engine) is either detonation or valves..

If the car was tuned on a hot day, (say 90 degree's out) a change in weather (say 30 degree's) could be enough to cause your car to run rich....depending on how rich the mapping was.....
It sounds like an overly rich condition, by the symptoms, but a lean condition by the sounds you describe (rattle)....