@Renos,
as JJJoseph says, this liqui-oily stuff down there in your vertical hose with the plug in it is, mostly condensate from your "motor breathing", and is an emulsion of water and lipoids. Sucking in a lot of fresh air for combustion means (amount depends on your environment) a lot of moisture which partially comes back via those tubes from valve cover and from your gearbox too.
The reason for his blocked one might be, that Kymco uses this airfilter box for other models with an different setup too.
Changing from mineralic motoroil to a good syntetic one brought in some cases a minimizing of oil consumption.
Recently read in some other tread and another forum too, that, if you overfill your gear, it might lead to increased oil assambly in this pipe.
So, do NOT fill your gear oil until that upper filler screw but follow your owners manual, which says in most cases of smaller scoots an amount 180 ml gear oil.
