The oil return needs to be moved to the left side of the oil pan. But your major problem is that the oil return isn't steadily going down stream to the pan. The bump up in the middle is is basically causing the oil to pool up in the line, and causing the oil to back up in to the turbo. Not to mention with the bike on the kick stand where your return is positioned oil is close or hugher then the level of the turbo.
Here's how they should be. Must be on the left side of the oil pan, so your draining to the lowest point. Notice how on both pics the line comes out of the turbo and it's on a steady downhill run all the way to the pan. They never dip lower then the oil fitting on the pan.
It would also help if the center section of the turbo was "clocked" properly, and the drain flange was straight down at 6 o'clock instead of that angle it is on. Hahn turbo systems drain into the front of the pan like you have it, but their headpipes mount the turbo a little higher than we have seen on the Velocity kits. The other two things you need to keep in mind: the turbo centerline - that is, the impeller shaft- needs to be higher than the oil level in the motor so sometimes you have to adjust the oil level slightly to make this happen, and two - make sure your breather on the motor is clear. Any obstruction on the breather - like a slightly kinked hose - will prevent the oil from draining out of the turbo properly. And something as simple as putting the bike on a swingarm stand can sometimes put the bike at such an angle that the turbo fills with oil overnight while it is just sitting there. Rerouting that drain line to the side like Rob suggested is a good idea that should help . . .