Biomes
Discovery
TerraForged scans through all registered Biomes and only uses those that have been given the BiomeDictionary.Type.OVERWORLD Type in Forge's BiomeDictionary.
This Type was introduced in 1.14.4 to allow mod authors to signify that their Biome is suitable for Overworld generation as opposed to being specific to another dimension.
BiomeDictionary Types should be added some time before server start via a line like:
BiomeDictionary.addTypes(myBiome, BiomeDictionary.Type.OVERWORLD);
Terrain
Due to TerraForged's approach to generating the world's heightmap, Biomes do not contribute height/variance as they do in the Vanilla (and most other 'normal') world generators. As such, modded Biomes may not look as the author intended.
Surface builders, features, ores, structures, carvers are used as normal.