I had a similiar case with my turbo too. Running a PT61 with the Cartuning kit and had it rebuilt by g-pop shop before I put the used turbo kit on. I'm running a restrictor and had the same questions. I called up G-Pop shop and they said that some is to be expected. I'm going to keep checking every couple of month for any additional shaft play since it has a 1-yr warranty. If it's a light hazing I was told it was to be expected. I'm running the supplied drain kit from Cartuning which has a 45 degree bend to start with a straight shot to the oil pan after that.
Edit...was also told that if you are running to much oil pressure that the first seal it's going to blow by is the exhaust side and you'll see that your car is burning a little bit of oil.
