I'm glad someone finds it as interesting as I do! It was plain ol' luck that I found it on Craigslist, in a nearby town, particularly since the seller had it listed not as a trailer in the heading, but as a carriage! Thankfully he had a picture, and so I called him to buy it immediately, even though I knew absolutely nothing more than what I could discern from the rather crummy pic.
Once I set the buy, I went onto the web to find out what I had committed to, and ran across this webpage as the best source of info:
http://www.totalbike.com/news/article/288. In fact, I could hardly find anything else aside from a few mentions on this and another bike forum, and mostly to note it was no longer in production. The owner informed me that he bought it directly from the manufacturer, at the now defunct
www.lodrag.com, website. He was told at that time that he was getting only the fifth one yet made. I have no idea how many were made in total, nor when the manufacturer, apparently VMS Industries, quit making them.
The website above covers just about everything, except that the hitch utilizes a thick rubber cylinder to get the flex necessary. It's a simple pin and cotter attachment to the chainstay mounting bracket.
Here's an unedited video I just made addressing some of the questions and showing a bit more of the functions and features. Forgive the amateur quality!
http://www.youtube.com/watch?v=498B9nu4kVc
Oh, and Masiman, yeah the girls are each just a few months either side of 4 years, and mine, after a short 3 mile ride, admitted it was comfy. The are slung between the frame stays, and above the floor, so I guess there's some give and passive suspension.