I'm familiar with the basic puzzle ring.
You say this is not the "standard puzzle ring".
. . If you're referring to one I know, I can't help you.
And I'm not familiar with any variations.
In the second picture, it certainly looks like the one I know.
We hold two of the rings as shown in the photo.
Then manuver the other two rings so they form a figure-8
. . around the lower portion of the ring.
Then we ease it into the upper assembly.
An interesting bit of folklore about these puzzle rings . . .
Legend has it that knights put these rings on their wives before leaving on a crusade.
They became known as signs of marriage, and no man (so they say) would dare have
. . an affair with the wife of a knight. .If an errant wife felt amorous, she'd have to
. . remove the ring ... and, of course, would not be able to reassemble it.