I live in SE Pennsylvania and havecable access to 3 PBS stations in my general local. One is in Camden, NJ, one is in Philadelphia, and one is in the Lehigh Valley (Poconos). If you need to know which one I've been watching, e-mail me DIRECTLY, but for the last few weeks, I've been following the re-construction of a home and barn on the TOH program on Saturdays and Sundays. This particular program is currently featuring Steve and Norm putting the finishing touches on the wood shop which has skylights flashed-ready for the new 100 year metal roof. The roof 'bending' equipment was brought on-site and the roof was basically custom-made. The pre-flashed-ready skylights to go with this particular type of roof looked like Veluxe. They used a special 'machine' to crimp the metal roof sheets to each other as well as to the window flashing. Of course, before installing the roof, they applied a type of snow-and-ice shield around the windows to seal out water.
I can't say for sure if you're gonna get your answer on this FORUM but if you went to This Old House, you may be able to get in touch with someone there to get you started as to how you can get your answer. At worst, let me know if you need further help and I can put you in touch with the proper PBS org that's currently broadcasting the application of the metal roof. Hopefully we're talking about the same 'stuff'. I guess the only way to find out is to ctc This Old House or the PBS org to see for sure. I'll be standing by.