Mary,

I have very little big cat experience, but..

If you are below with hatches closed during a capsize, is it common that floor boards etc. are secured so they dont hit you together with all the other loose stuff?
For a capsized multihull to be safe/possible to survive in, dont it need to be designed with this in mind with dry bunks when inverted and a way to stop surge? Isn't a emergency hatch for use when inverted also more or less a prerequisite?
Did the boat in question have these safety measures?