well, the vertex groups of the file has some unknown bones that are not in the armature and some are mixed up like the left parts and the right parts of the costume, the seem torn up when moving the bones.
I found out why the vertex weights are incorrect.
In the case of the costume model, the bone ID specified by the vertex weight seems to be the bone ID of the model who wears it, not its own.
I never thought that the costume model alone would not give the correct bone names from the bone IDs.
This fix will take quite some time.
When I select the ism2 file, I need to specify another ism2 file, but I have to find out what to do for that.
Thank you for telling me why the character is shrinking.
There is also a motion that the finger keeps rotating, so it seems that there are many things that need to be fixed to get the correct movement.