I had the M coupe up on the lift today looking for any oddities. After a brief inspection, it appears to be a little wet near the oil drain plug. So, after taking the protective pieces away I think I pinpointed the issue. My first thought was oil, but after some research I think it might be water per the rust present around the area.
*** Update *** Fixed ***
The issue was part number 11-11-1-318-185 (Constant Pressure Value). This particular part is prone to fail due to the o-ring heating up and deteriorating over time. The part is about $35 from the BMW dealer. If you have the right tools, you might be able to replace yourself.
I believe the correct items are #9, and #10 in this diagram: