Hiya.  I just built a new model, and as always the "mask" of the eye covers the "white" of the eye, but the iris can barely move.

I had this happen to me when I did my first custom head.  The left eye of my character had a lazy left eye and barely moved.  I never found the root cause of the issue, but I went back and redid the entire head using the Martha model as a guide.  I carefully replaced each component one by one and after reimporting it back into CA4 it worked.  It could have been the first time I had something additional in the folders that CA4 didn't like (more than one png file in a specific folder).  That has bit me more than once.  I'm no expert, just a user.

I experienced the same problem.
Not sure why it happened. 
Sometimes, the eye movement did not co-ordinate. 
I thought that I might do something wrong somewhere. 





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