I saw an example where the modeller had inserted small dowels between the bulkhead frames, closer to the ends of the frames than the keel. It looked very stable visually, but I can't imagine the amount of precise measuring that went on to get that rigged up. Still, based on the examples I have seen I am starting to appreciate the necessity of a square and robust hull assembly!
What is your take on the use of pins to hold the deck and planking in place? I notice some use pins and leave them in permanently, others remove them once the glue is set, and some don't use pins at all. The AL BN II instructions advocate pins, but there doesn't seem to be a really clear directive on their lifespan.