Equiping "Equipment" in Ancestor Trials

I feel like an absolute idiot, but I am having problems equipping "Equipment" I purchase for favour.
Equipping the "Field Items" seems simple enough, by dragging them to a position on the field. But when I try to drag an "equipment" item to one of my warriors, nothing happens, the item immediately falls back into its place from where I tried to take it. I must be overlooking the obvious, since a search for my problem turns up nothing, but I am seriously misreading the UI. Can anyone give me a tip for an absolute idiot? I've managed to win some tournaments without the "equipment" I bought, but it sure is annoying.

You cant equip anything while the warrior is placed on the board.

Gotta remove him from the board and then equip the item.
Or equip the item while you are talking to any of the NPCs in the hall. Thats works too.

While it's easily missable, you can also move around equipment anywhere in the hall. The windows listing your warriors and equipment are both minimized while you're walking around the hall of the dead, but you can click the buttons on the left/right edges of the screen to bring them up.

Thanks much.
Unbelievable how it's possible to miss this. Would be nice if the UI were upgraded if this were to become a core mechanic