Hello, I'd like to make a custom armor, which uses different armorAddons, but there are some issues: some armorAddons are not displaying in the CK.

So I have these objects in the Creation Kit:
an ArmorAddon object called "myBodyArmorAddon" (with BODY(32), Forearms(34) and Calves(38) biped objects selected), which covers the full body (I used an already made nif model)
an ArmorAddon object called "myMiniLantern" (with Amulet(35) selected), which shouldn't cover any bodypart, but it's just an addition to the fullbody armor, I chose "Amulet" slot for testing it.
an Armor object called "myBodyArmor", which has the "myBodyArmorAddon" and "myMiniLantern" pieces in its "models" section, and BODY(32), Forearms(34) and Calves(38) biped objects selected.
...(I'd like to add other ArmorAddons, but I'm testing it with just the lantern now)

So the problem is that the minilantern is not displaying, whereas the fullbody armor is visible, and if I delete the myModyArmorAddon from myBodyArmor piece-list, the lanter is displaying (that is my two armor addons cannot be used together, but they are visible when alone). I also tested the minilantern using the BODY slot but it hides the original npc naked body if so, displaying the lantern only.

I don't want to merge the armor addons into one single armor addon cause then I'd like to make a script that changes my myBodyArmor's ArmorAddons in its Models list (I still have to read Papyrus tutorials, but is there a function or a way to achieve this, is it possible?)

Which correct "biped objects" slots should I select for my three aforementioned objects?

What is the difference between the Armor "biped object slots" is using and the ones used by its ArmorAddon objects? (I used the same three slots for myBodyArmorAddon and MyBodyArmor, but the minilantern uses Amulet, which is different)

Which bone/node does the lantern mesh need to be attached to in Nifskope to use it as an Amulet slot? (How) should I specify in Nifskope the bodypart I want it to use? (I pasted the lantern to an already-made body model in Nifskope and then deleted the bodymodel and kept the lantern only)