Blow-by system basics

I had some spare time the other day and decided to read the Guzzi parts catalog in the hopes I might learn more about these machines and came upon the "blow-by" system.  I have a general understanding of the purpose but was curious about two parts in particular and how they function and was hoping for some clarity.  First, what is the "box" type of thing under the steering column and what purpose does it serve? Secondly, the one line that goes to the oil pan....I don't quite understand how it functions. Are these lines filled with oil or just there to handle vapor?  If so, is there any cause for concern if there is a little seepage from where the indicated hose connects to said box?  I don't have any leaks, but I came across someones post here and and an article online that said these lines can get clogged sometimes it got me curious. Thanks in advance!

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The box is there to 'disentrain' oil particles that are being carried in the blow-by gases that are coming from the two crankcase via the cam tops (numbers 16). Idea is that big oil droplets fall to the bottom & return to the sump via the pipe that you arrowed going back to sump. The 'slightly less oily' gases then go over the top to the air intake box & then get burnt to avoid emissions.

All vehicles have these type of closed routings for blow-by gases since many years when they used be open loop and run to atmosphere through a road tube.

Maybe should add what 'blow-by' is....when engine is running there is a leakage of gases from combustion chambers down past the piston ring set. These gases carry partially combusted mixture and some oil (they flow past oil control ring) plus oil already floating in crankcase. This obviously result in a positive pressure in the crankcase that has to be relieved to avoid blowing seals etc; hence need a venting system for blow-by and unless you want to create emissions with the oil & vapours, it has to be recycled into inlet system and then burnt.