It's not me, I haven't done it
If you track back the messages you'll see that It's Nick on RASCAL.
My guess is that his exit hose just goes where the standard galley sink drain goes into the grey water sump.
My idea was to go straight into the sea, but maybe a shower sump might be better and then pump out to the sea.
A macerator pump will just turn the waste into smaller pieces, it would still be in the grey water sump and that's what I'd like to avoid.
Anyway, good discussion, lots of ideas....keeps the mind working when I can't get near Elyse.