Hi Leon,

On my Yost Sea Cruiser I glued and screwed the West Red Cedar longitudinals to the plywood frames; when the glue had hardened I removed the screws and glued in dowels as per Tom Y's suggestion. If there is ever a second craft I would probably follow Jeff H's suggestion and just lash with synthetic sinew - much more simple and you can do one or two connections each building 'period' rather than have to rush to get the connections all set-up before the glue hardens.
I put epoxy resin on the whole plywood frames but, after due consideration of the properties of marine grade plywood and the glues used in its manufacture, next time I would apply epoxy to only the edges of the ply (particularly in the "notches" for the longitudinals) to provide a good timber seal and just oil the other surfaces (used Tung Oil).

Re glue, I used epoxy glue (Aust manufactured BoteCote) for the hull before I "discovered" TiteBond III near the end of the build - Thanks Jeff H. for the on-line video on coaming building and the use of TiteBond III !

Good luck with your build,
Cheers, Martin B.