Thank you for the suggestions. As for your points:
1) I have no experience with the workshops (and honestly hardly any with DF), could please you provide the workshop for me?
2) Regenerating almost every time. Pocket world takes less than a minute to create.
3a) plants are in plants_custom.txt, the blood boils and cave vines are in there too and work just fine, as does the growing and processing of the mithril cotton. The only errors I have right now are the graphical tiles are solid blocks at the moment.
3b) I've checked and double checked and triple checked. The only way I can think I'm screwing this up is if I'm referencing the thread wrong. I'll post the code anyways so that you can make sure I'm not screwing up.
3c) This, I know, works. I can process the thread into cloth, and that takes the 15000 thread.
I'll try working on those "free" reactions in a moment. Right now, the code:
[INORGANIC:MITHRIL]
[USE_MATERIAL_TEMPLATE:METAL_TEMPLATE]
[STATE_NAME_ADJ:ALL_SOLID:mithril]
[STATE_NAME_ADJ:LIQUID:molten mithril]
[STATE_NAME_ADJ:GAS:boiling mithril]
[DISPLAY_COLOR:1:2:3]
[MATERIAL_VALUE:35]
[SPEC_HEAT:130]
[MELTING_POINT:11915]
[BOILING_POINT:15141]
[ITEMS_WEAPON][ITEMS_WEAPON_RANGED][ITEMS_AMMO][ITEMS_DIGGER][ITEMS_ARMOR]
[SOLID_DENSITY:200]
[LIQUID_DENSITY:2600]
[MOLAR_MASS:55845]
[IMPACT_YIELD:1200000]
[IMPACT_FRACTURE:1200000]
[IMPACT_ELASTICITY:720]
[COMPRESSIVE_YIELD:1200000]
[COMPRESSIVE_FRACTURE:1200000]
[COMPRESSIVE_ELASTICITY:720] 160
[TENSILE_YIELD:750000]
[TENSILE_FRACTURE:1000000]
[TENSILE_ELASTICITY:750] 200
[TORSION_YIELD:750000]
[TORSION_FRACTURE:1000000]
[TORSION_ELASTICITY:750]
[SHEAR_YIELD:750000]
[SHEAR_FRACTURE:1000000]
[SHEAR_ELASTICITY:750]
[BENDING_YIELD:750000]
[BENDING_FRACTURE:1000000]
[BENDING_ELASTICITY:500]
[MAX_EDGE:30000]
[ITEMS_HARD]
[ITEMS_METAL]
[ITEMS_BARRED]
[ITEMS_SCALED]
[WAFERS]
[PLANT:COTTON_MITHRIL]
[NAME:mithril cotton][NAME_PLURAL:mithril cotton][ADJ:mithril cotton]
[USE_MATERIAL_TEMPLATE:STRUCTURAL:STRUCTURAL_PLANT_TEMPLATE]
[MATERIAL_VALUE:3]
[BASIC_MAT:LOCAL_PLANT_MAT:STRUCTURAL]
[PICKED_TILE:3][PICKED_COLOR:7:7:0]
[GROWDUR:500][VALUE:4]
[USE_MATERIAL_TEMPLATE:THREAD:THREAD_PLANT_TEMPLATE]
[THREAD:LOCAL_PLANT_MAT:THREAD_METAL]
[MATERIAL_VALUE:15]
[USE_MATERIAL_TEMPLATE:SEED:SEED_TEMPLATE]
[MATERIAL_VALUE:2]
[EDIBLE_VERMIN]
[SEED:metal nut:metal nuts:7:0:1:LOCAL_PLANT_MAT:SEED]
[SPRING][SUMMER][AUTUMN][WINTER]
[FREQUENCY:100]
[CLUSTERSIZE:5]
[PREFSTRING:silver threads]
[WET][DRY]
[BIOME:SUBTERRANEAN_WATER]
[UNDERGROUND_DEPTH:1:3]
[SHRUB_TILE:58]
[DEAD_SHRUB_TILE:58]
[SHRUB_COLOR:7:0:0]
[DEAD_SHRUB_COLOR:0:0:1]
[REACTION:MITHRIL_WAFERS]
[NAME:make mithril wafers]
[BUILDING:SMELTER:NONE]
[REAGENT:A:15000:THREAD:NONE:PLANT_MAT:COTTON_MITHRIL:THREAD]
[PRODUCT:100:1:BAR:NO_SUBTYPE:METAL:MITHRIL][PRODUCT_DIMENSION:150]
[FUEL]
[SKILL:SMELT]