hoshi911: Black to play.
It seems to me that there is an alternative correct solution (for one
branch) which is currently labeled as incorrect.
After the sequence
b N6, w N2, b N5, w L2, b M1, w L1 only b M4 is allowed. But if instead b K4, white is also dead due to similar reasons. A possible continuation after b K4 could be: w N1, b M4.
Ivan Detkov: I agree. After M1 all stones are dead. There are too many continuations after L1. One of the best is H3 for example. I decided to cut the sequence at M1.
Black to play. It seems to me that there is an alternative correct solution (for one branch) which is currently labeled as incorrect. After the sequence b N6, w N2, b N5, w L2, b M1, w L1 only b M4 is allowed. But if instead b K4, white is also dead due to similar reasons. A possible continuation after b K4 could be: w N1, b M4.