Without any mods that add new biomes, ZAWA will mostly use the Biome Dictionary to determine where to place entities. As long as biome edits arent disabled in the main confg, ZAWA will handle all incorrectiveness (based on vanilla biomes).
minecraft:hell, minecraft:sky, biomesoplenty:volcanic_island, biomesoplenty:corrupted_sands, biomesoplenty:fungi_forest, biomesoplenty:phantasmagoric_inferno, biomesoplenty:undergarden, biomesoplenty:visceral_heap will always be removed from all ZAWA entities, however each of these can be added back to the spawns with the config.
Traverse and Biomes O' Plenty
If either Traverse or Biomes O' Plenty is installed, ZAWA will do the same that it would do if it was standalone by editing what biomes the animals spawn at to fit the biomes of either of these two mods properly.
Other Biome Mods
ZAWA currently does not support other biome mods for Biome Edits, however as long as the other mod registers their biomes with the Biome Dictionary ZAWA animals will spawn there.
The chance is the weighted probability that the animal will spawn based on other animals in the world. This is handled by Minecraft and NOT ZAWA, for more information look into how Minecraft handles entity spawns. Min and Max are the min and max entities that can spawn in a group respectively.