The graphic is wrong, I should have shown the valve open, but I don't see how there's any way to empty the sight tube unless the tank is empty.
Keith said the oil was poured in through the sieve. Are you saying it's pumped in? Or have I got the wrong end of the stick again?
I agree that could be stated, but to keep things consistent with the other processor pages, this one could do with a step by step text, if KH agrees. The notes in the state diagram were only really intended to be very brief. Hence my comment somewhere above.
How do you mean unfinished? If you mean the dotted boxes, I didn't notice those last night ... I've just got a space in the wrong place somewhere which I'll try and sort out later.