I ultimately decided to compile what amounted to nightly builds each month for the time being for my hack, but I'm going to need help with the script where Misty teaches your Pokémon Iron Tail after you win the rematch with her in Celadon City. Here's what I have thus far:
CeladonCityAfterBattleText: ; 48a95 (12:4a95)
TX_ASM
CheckEvent EVENT_IRON_TAIL_TUTOR
jr nz, .asm_7053f
ld hl, IronTailMoveTutorPreText
call PrintText
ld a, 5
jp CeladonCityTutors
Basically, I intend to have the game check if any Pokémon in your party can learn Iron Tail. If no Pokémon can learn Iron Tail for whatever reason, Misty will tell you to put a Pokémon in your party that can learn Iron Tail. If at least one Pokémon can learn Iron Tail, the Move Tutor script will proceed as usual. After successfully teaching the move, the player will move one step down, Misty will move one step left, and her sister (Lily, for whom I'll use the Foulard Woman sprite) will move one step down, out of the Celadon Ballet Academy, after which Misty will comment on it before the two leave Celadon.