From Dark and Darker Wiki
Gear slots are not a factor in gear score so 1 common campfire is still worth 4 GearScore
Bolts and arrows are misc items and do not have Gear Score
诗人乐器算什么呢 - 公用事业 (Bards Instruments? - Utility.)
I just checked and Rubysilver vestments are not bugged, they are worth 30 GearScore just like the other Epic chest pieces.