Many itchy hours later...
We've just spent a week and a half in the shop (8 to 12 hours a day) laying fiberglass, grinding, drilling, and all kinds of very manly things! There was no time for pictures or updates... Slowly and painfully we saw the pieces getting finished... It was hell! Every arm (and we have 24 of those) had to undergo about 10 steps before being entirely finished.
We got help last weekend from Justin, Matt, Will, Jimmy and Emily. All of you really helped us quite a bit!
Everything asks for a creative solution. A bundel of garden hose tubing will serve as damper for the joint between two levels... Long live Home Depot!!!