Item without CanCarry flag prevents shield autoequipping in dark areas
This bug is easy to reproduce with Mage Robes mod: https://www.nexusmods.com/morrowind/mods/45739
coc "vardarai, the gushing grotto"
The NPC nearby - Gorluck - unequips his mining pick (which keeps Shield slot). That's because he has the "mg_light@_flame" light in inventory without CanCarry flag.
Possible solution: ignore lights without CanCarry flag in updateEquippedLight().
(RM-4457 from redmine: created on 2018-06-16 by Andrei Kortunov, )