If you look at the top of the canister that has the yellow knob you will notice that it says "oel". Say it aloud, sounds like oil doesn't it.
It German for oil.
As for the hatch, it has adjustments but most of the time it is worn out. They can sometimes be shimmed to get them working for awhile but it will need replacing eventually. Check the part of the latch that is in the hatch ( top half of lock). Sometimes the sheetmetal housing will get a small crack in it and cause the symptom you are seeing.