File type and hierarchy (most common files for swapping), and what do they do:

CCI: Calls the CI files and contains MI data (making an item colorable or not, also has the colors slots). CCIs can affect material properties like metalness.
CI: Calls the SK files. CIs determine in which item category a mesh belongs, e.g. upper or lower.
SK: Contains a Mesh and Calls the MI files.
MI: Contains Material data and Calls the T files
T: Contains Textures -> defuse, mask, normal (there are other textures too like ambient occlusion and specular). .... ... .. .

Other files:

SKT: SKT stands for skeleton which gets referenced by skeleton meshes, this file can be found inside SK files.

Important note: Jack7, alisa, kazuya use different SKT, everyone else uses the same SKT.

Important note: for the purpose of modding it's wise to avoid messing with the M's or their specific textures directly.

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