To put it simply: your task is to assemble a MOD, but you cannot buy the components of this artifact on the market. Also, you cannot use the ring that is in one of the chests.

Please provide a link where this is stated. I personally understood that if I come across these artifacts somewhere, I have every right to use them!
It's a different matter that I cannot finish the game if I have collected all the parts of the assembled artifact somewhere, but at the same time, I have not completed the required quests to collect these artifacts. So far, I know that I can only NOT use the Boots of the Dead and the Orb of Negation (by the way, I was looking for it :))

Added after 16 minutes

And yet, if any shortcomings are found in this map, please immediately report them to the email address VDV_forever@BK.RU, or VDV_forever@heroesworld.ru. After all, only those who do nothing make no mistakes, and judges, as well as organizers, are no exception.
Sincerely, VDV_forever

:), VDV-forever, change the wording of this phrase: "After all, only those who do nothing make no mistakes, and judges, as well as organizers, are no exception."
It implies that the organizers and judges do nothing and do not make mistakes. Isn't that what you want to say?