Hi
I'm building a Banckert too and was reading your stream with interest. I made my hull and deck from fiberglass, using the supplied ones as molds. It worked well for me. I sealed the hull-deck joint with silicone and used sealing film/release agent to make it easy to re-open for maintenance. The motor I used is a 400 which pushes her pretty well. Not a real duck scarer but fast enough. The first launch ended in a sinking as I hadn't yet sealed the hatches properly and it took on lots of water in the choppy waves. I jumped in and rescued it as the bow was going under!
It's now very waterproof and hopefully won't sink again. The following link is to a pic of it at it's current stage of building, or you might like to check out my web-pages on the build at the second link.
http://magpieyachts.com/Tugflybridgedonepainted.jpg[/link]
www.magpieyachts.com/building4.html
Scroll down to see the Tug article.
There's also 2 videos on the second page of it; 1 on the first sea trial and one for the second with a better motor and sealed hatches.
Regards
Jason (Australia)