LeatherScrollProblem133/Attempts

I am at a loss to understand how White should live here. My first thought was the naive pushing chicken leg sequence. There seems nothing in the sequence a' to d''.

White not living 1  

on varying a little I am equally lost, there seems no time to do anything

White not living 2  

The other obvious starting point is the wedge, but as soon as I started I stopped

White not living 1