Thanks to everyone who chimed in with help on my blocking and snagging questions. My first ever Russian Orenburg shawl is complete, and it's great! (Full credit must go to Galina Khmeleva, author of the book *The Gossamer Webs Design Collection: Three Orenburg Shawls to Knit,* who not only sold me the book but also the beautiful yarn.)
I took Tamar's advice, and repaired the snag before blocking. I looked for it just now, and I can no longer find it.
Then, after gawking suitably at the gorgeous lace (and careful blocking) shown at the site DA posted, I finally got some time (and my courage) together, and pinned everything out last night.
I did find some nylon cord, and I tried using that method only, but it didn't work very well. It made the pinning a bit easier and perhaps more even, but it's no substitute (and it's not at all "magical," as I'd once read in an article).
So, it's done. It's a rectangular wrap, in royal blue, and after blocking it's about 67 inches long and 28 inches wide. I plan to wear it to dinner New Year's Eve, over a black sweater, and I'm very very proud. Tired, but proud.
Thanks again, Claudia
PS: Regarding the question about the stretchiness of the alpaca/silk blend, I don't really have a good answer, because I've never knitted with pure versions of either. I will say that this blend is not particuarly fuzzy, so in that sense it's more silky, but it's pretty stretchy, so in that sense it's more like the alpaca. It's quite light (I worked it on US 0 needles), and it's very soft.