The 22/45 is designed to so thoroughly mimick the .45 experience that it lets you mar the frame the first time you re-assemble it.
Take it apart and try again, making sure that the hammer strut is resting in the little detent above the mainspring. You should get stiff resistance only when the mainspring housing is about an eighth of an inch from flush with the frame.
Heh. Yeah, I suppose the experience is that
I'd love to take it apart and try it again... but my problem is that it will not come apart. The mainspring housing won't swing any farther out than shown in the above picture. It seems to be caught on something internally.