The issue appears to be resolved. Well, mostly.

I took it back today and spoke to their in-house gunsmith. I showed him the problem. At first he attempted to convince me that there was nothing wrong with the gun, i.e., that I should just manipulate the cylinder just right for ejection every time, so as to avoid the problem of the cartridge rims locking against the frame lug.

When I remarked that I have six other J-Frames from multiple periods of manufacture, and that none of them have this problem, he pulled out one from the same period and tried to convince me that the same thing occurred with it. I asked to try it myself, and showed him that no matter what position the cylinder was in, the rims completely cleared the lug with his specimen.

Now appearing annoyed, he agreed to take it in the back and examine the crane on mine more carefully. After twenty minutes, he reemerged with my gun and said the problem was solved. He handed it to me, open cylinder, filled up with empties. I ejected them, and discovered that he was right, i.e., now the rims clear the lug regardless of position.

I asked him what he did. He said he bent the crane. So I closed the cylinder, and it felt completely wrong and rough as it locked into place. I also noticed that now the cylinder release latch would only partially (about a quarter the way there) return to its rest position after closing the cylinder, and felt rough in operation.

I pointed these things out to him, and he angrily took it into his back room for another ten minutes. When he reemerged, that problem was mostly resolved, and the original problem was also resolved, as now the rims barely cleared the lug regardless of cylinder position, but just barely. That's good enough, though. The cylinder release latch, however, is now rough in operation while before it was smooth and satisfyingly clicky like it was supposed to be.

I guess this is the best I'm going to get from these folks. I spent money for what was supposed to be a like-new, 1970s vintage, Model 36, and now I have one that's been messed with quite a bit, and doesn't feel quite right in the operation of its cylinder latch.

That's life, I guess. You win some and you lose some.