Would be nice if we could go somewhere to get help for the config. For example, I am currently experiencing a issue with the "infection_conversions" json. I don't know why, but it seems I formatted the NBT wrong for these two entities, and it's messed up the whole file. Help on this would be nice, but I feel a discord would be useful for modpack devs.

{
"entity": "conjurer_illager:conjurer",
"converts_to": "minecraft:zombie_villager",
"chance": 1.00,
"nbt": "{Attributes:[{Name:"generic.max_health",Base:26f}], texture:"hordes:textures/entity/zombie_witch.png", chat_name:"entity.hordes.ZombieWitch.name", VillagerData:{type:none}, {ArmorItems:[{},{},{},{id:"conjurer_illager:conjurer_hat",count:1}]}}"
},
{
"entity": "goety:conquillager",
"converts_to": "minecraft:zombie_villager",
"chance": 1.00,
"nbt": "{Attributes:[{Name:"generic.max_health",Base:37f}], texture:"hordes:textures/entity/evoker.png", chat_name:"entity.hordes.ZombieEvoker.name", VillagerData:{type:none}, HandItems:[{id:"minecraft:crossbow",Count:1b},{id:"minecraft:firework_rocket",Count:64b,tag:{Fireworks:{Explosions:[{Type:0,Colors:[I;15790320, 15435844, 12801229, 6719955, 14602026, 4312372, 14188952, 4408131, 11250603, 2651799, 8073150, 2437522, 5320730, 3887386, 11743532, 1973019],FadeColors:[I;15790320, 15435844, 12801229, 6719955, 14602026, 4312372, 14188952, 4408131, 11250603, 2651799, 8073150, 2437522, 5320730, 3887386, 11743532, 1973019]}]}}}]}"
}

Also, it's a shame you can't specify the target for conversion to check for specific NBT data, like a variant or something for say a cat or axolotl.

Nbt and json work a little weirdly with each other, you have to add a backlash \ before every use of a quotation mark " in the nbt.

I'm working on a discord, I just haven't got it fully ready yet.

As for the specifying target per nbt, that's a pretty good case that I didn't really think of, I'll leave thise issue report open so that that can be added.