First of all, thanks for your thoughts guys. I did figure out what the problem was after taking the gun completely apart (what you see on the pictures was as far as I went so far).
The bolt spring was attached properly. However, the cylinder stop (I have a feeling I'm not calling it by its right name) has a tendency to misalign along the sights axis on my gun. Once the misalignment happens, the cylinder stop will not fit through the hole. This may seem trivial, but I did push it around before I made the original post, and realigning it is not trivial. Once realigned, the cylinder stop will go through the hole and stay there, retained by the bolt spring. However, if I attempt any firing before putting the side plate back on, the cylinder stop will immediately go out of alignment again. Once the side plate is on, it fits very tightly into the frame and holds the cylinder stop in place.
Darn, that was a tough one, although quite a learning experience.
Ok, so now that I have it all there (and no leftover parts hehe), maybe someone could help me with another issue. This is an airlight, and not only that, but it's one of the very early ones with an aluminum cylinder. I heard that S&W has recalled those almost right away, because they tended to burst. Should I replace the cylinder with steel one before attempting to shoot it? The gun has been shot at least some, before I bought it. Of course I'm not thinking of shooting any +P ammo, I was thinking of just trying out the standard 130 grain Winchester load.
As far as you can tell, is there a possibility that the titanium cylinder from a new Airweight would fit as a replacement?
Just to make this clear, unless I heard otherwise I was just going to play it safe and not shoot anything until I got the cylinder replaced, and I was going to order the steel replacement and not risk havingto return a titanium one. Come Monday I'm hoping for a nice chat with S&W historian, Mr. Roy Jinks.