mainstream

Hello,

My car is an 2008 525D and it has around 70 000km(43500miles) on the odometer.
The other day I noticed that half of the cover underneath my engine was smeared in oil, and I have to admit that this is something that I don't check out often enough. (practically haven't even looked at it since I changed tires last fall)
Apparently the oil seems to have originated from the charge line going into the intercooler, and it must have been going on for quite some time. There was up to 5mm with sand/oil on the cover for reference.
I'm not that much of a mechanic, so I've had to resort to googling and calling friends.

So; what could be going on?
I've talked to the workshop I had the car at the last time, and they claim that they changed the crankcase ventilation filter in October.
I live very far north in Norway, and the mechanic immediately had a theory that the breather had frozen sometime during winter. Perhaps the valves have locked themselv into place due to that?
I'm really hoping it's just the breather unit and that my turbo isn't ruined. The worst thing is that I can't get it looked at before the 4th of June.

I uploaded pictures of the couplings and the cover to Imgur. Sorry about the crazy angles.
525D - Imgur
imgur: the simple image sharer

Does anyone have experience with cases like this, and got some valuable tips on what I can do to check this out on my own?