I'm still not sure how to know which numbers I have to use so I just randomly selected them
but at least it worked.
Basically, the logic behind assigning cut numbers is that we start from the "bottom"
As you see, the one meant for hats that are placed on the head the lowest is 0000, the one for higher placed hats is 0001, the main shape is 0002
If you do not want to make your hair compatible with hats, you need to just delete the original 0000 and 0001 meshgroups, duplicate the main shape twice and assign cut numbers to them, does not matter which one to which meshgroup
As for the blend you shared, it has one meshgroup which cut number is 0003. In this case s4studio_mesh_3 should have 0000, s4studio_mesh_1 - 0001, s4studio_mesh_2 - 0002. Also, you should delete all these rig.001-7 (leave the original rig), they are not needed.
There are problems with a uv_1 map and weights
How to fix the weights:
- in Edit mode disable Limit selection to visible. Holding Ctrl, select this.. thing like i did, choose head vertex group and click Remove, select neck vertex group and hit Remove again, switch to Weight paint and click on Auto Normalize. ( for the future, this works only if the meshgroup has Armature modifier added and rig selected, yours already does)
As for your uv_1 map, it's best to separate the braid fully and transfer the uv_1 map for it from the body
- choose uv_1, enable sync, select the braid;
- in 3d view press P and choose Selection;
- unfold rig, make top selectable;
- add Data transfer modifier to the braid, choose top as Source object, set the rest like in the pic, apply;
- join the braid and the rest