It is indeed in my neck of the woods (about 30km from where I live). And somewhat irritating as I was looking for that last year. It was a gathering of carpenters who (IIRC) would erect a timber frame using traditional (read medieval) methods. I had been hoping to go as a spectator, but the person who told me about it couldn't remember where it was or who organised it and I never managed to find it. Thanks for the link.
If I can work out how to use the horse to get the timber 7m up in the air, then I'm game to give it shot.
Back in the world of reality, I'm currently investigating a rework of the frame, using hardwood splines and having the beams all joining posts rather than passing over them. This eliminates the scarf issue (both in SU and in the real world). This being my first attempt at such work, simpler is definitely better.
Thanks again for the link. I'll have to watch the rest of the videos. If you've already seen them and need any translations, feel free to PM me.