Ok, those worked. Thanks.
I had a play of it. The levels seemed very out of order, difficulty-wise. At least, to me, the earlier levels of the 4th set were MUCH harder than the later levels. Seriously, what is 4.11 doing in set 4? Or 4.13? (Assuming, of course, I did it right. The hint insinuated that I did, although I later went to set 3 and passed the level in that set in the exact same way.)