I am aware that unfortunately these chess problems are probably a little bit to hard to solve for hobby chess players - but it is not easy to create quizzes which are interesting for the advanced players as well as for the beginners at the same time ...
Sure I am chess master: I still remember these good old days when Kasparov begged for a break after I just had beaten him seven times in a row. :-) Just kidding, I was a strong chess player playing in the second division of Germany and taking part in some chess opens, but finally decided it was too time consuming doing it professionally as the financial reward is comparatively low in relation to the invested time (chess players are no soccer or basketball stars :-) ).