wow that is a horrible mess, I'd suggest for your sake of debugging to look into how [SELECT_ADDITIONAL_CASTE] will help quite a bit, you are constantly redefining other tags (I think I saw HOMEOTHERM 3 times?)
I'd say do a quick find for these tags:
CARNIVORE
BONECARN
HUNTS_VERMIN
to ensure that they are the culprit, as I know HUNTS_VERMIN might be the biggest cause. Also for a little pointer, I saw your dwarves are using standardized materials yet they still have [USE_MATERIAL_TEMPLATE] in them also typo in Black Mages bone spike spells, the first one is "spit a bone pike:spits a bone spike" and several mages have spells in the wrong headers (or maybe black mages) where they use [SELECT_TISSUE] and alter the values, you do know that changes the tissues for all of the castes? Tissues and Materials are CREATURE level, not CASTE
here is some hints at how to fix some things:
[CASTE:FIRE_1_M]
[CASTE_NAME:ashkin:ashkins:dwarven]
[DESCRIPTION:*ASHKIN - FIRE LVL1* This dwarf bears a spark of magic in him. A fresh member of the school of fire, he has learned to withstand intense heat. He can throw balls of flame at his enemies Being arcane in nature he can still cast his magic conceal spell. He is a novice in the use of the fire staff. If carrying a fire aura, he will cause blisters and pain in all nearby enemies.]
[MALE]
[CASTE:FIRE_1_F]
[CASTE_NAME:ashkin:ashkins:dwarven]
[DESCRIPTION:*ASHKIN - FIRE LVL1* This dwarf bears a spark of magic in her. A fresh member of the school of fire, she has learned to withstand intense heat. She can throw balls of flame at her enemies. Being arcane in nature she can still cast her magic conceal spell. She is a novice in the use of the fire staff. If carrying a fire aura, she will cause blisters and pain in all nearby enemies.]
[FEMALE]
TO:
[CASTE:FIRE_1_M]
[MALE]
[CASTE:FIRE_1_F]
[FEMALE]
[SELECT_CASTE:FIRE_1_M]
[SELECT_ADDITIONAL_CASTE:FIRE_1_f]
[CASTE_NAME:ashkin:ashkins:dwarven]
[DESCRIPTION:*ASHKIN - FIRE LVL1* This dwarf bears a spark of magic in her. A fresh member of the school of fire, she has learned to withstand intense heat. She can throw balls of flame at her enemies. Being arcane in nature she can still cast her magic conceal spell. She is a novice in the use of the fire staff. If carrying a fire aura, she will cause blisters and pain in all nearby enemies.]
you have custom descriptions of He and She might as well scrap that, I'm sure players can read the dwarves stats and find the gender. By using "this dwarf" and "they"
I'd also just redo your entire Dwarf creature with the stuff that all castes should have at the top then caste special stuff, then interactions/spells I'm sure 4000+ lines can be cut in half effortlessly if not close to, since alot of it is duped raws.
Also as for my example if you want to keep the He and She descriptions that is fine, however for interactions and spells do they really need to be separate? I don't think there is a male or female related magic, everyone can cast the same spell regardless of gender. Just saying.
I'm still looking for what could be causing the issue of not eating, it could be [BLOOD:] as if the surrounding tempeature is hot enough to boil their blood or damage it, they will consider it HOT or they might consider it COLD basically thinking "This place is too dangerous, I shouldn't stay here" thus won't really eat or drink due to thinking it's dangerous. Had that issue with automatons that has steam as blood (when I used a custom water materials, not WATER)
EDIT::
just saw
[SELECT_MATERIAL:ALL]
[MULTIPLY_VALUE:3]
[COLDDAM_POINT:NONE]
[HEATDAM_POINT:NONE]
[IGNITE_POINT:NONE]
[IF_EXISTS_SET_MELTING_POINT:15000]
[IF_EXISTS_SET_BOILING_POINT:20000]
won't do anything, materials are standardized, and if it did work all dwarves are fire proof.