Yes, vermiculite is the stuff that looks like insulation under the teak.
No, the Aussies eat Vegemite on their sandwiches. I've tried Vegemite... once... and I think I'd prefer eating a sandwich of wet vermiculite.
On hull #337, the area under the vee berth does drain into the bilge. There is a limber hole in the teak where it meets the glass floor of the head. This regularly gets clogged, but jabbing around in there with a wire fishing aft will generally clear the clog so that it can drain aft to the area under the head floor, which in turn drains aft into the main bilge. This does work... but as with any boat, debris tends to clog the limber holes and narrow spaces where the water is supposed to flow.
