for 15 just hold the yellow one so the box hits the ground not the green one and opens, keep holding so all the orange ones go into the finish, might have to release the button for a second at some point
i just had a strange bug, i died on the second boss, not on the boss itself but the mob i was fighting before while the boss came, then as i died the boss died for no reason too and after i killed the other mob i won O_o
on a german keyboard layout it is this:
/ is #' (next to return)
= is +*~ (net to return)
rest of the keys are normal.
you can press them immediately after pushing start.
here's a list in order:
B9P/1=MR up .H down Q5 home WX
you have to click on the top or bottom part of the boxes you want to change (the letter boxes as breaker or the number boxes as maker), that should be added somewhere, it's a bit hard to find out.
also, you can't cheat the computer by changing the permutation while giving hints :P