Could you please try if the following work-around works for you:
Browse to "Skins"-(sub)folder.
Rightclick on skin-file you'd like to change to.
Select "Change name" and change extention .bsz into .zip.
(If asked for confirmation click "Yes")
Now extract .zip-file into a folder of its own name (inside Skins-folder).
Start-up BSPlayer Pro and try to change the skin.
What happens?
P.S.: You didn't give any response to my remarks:
from skin ? to skin ... [I meant skin-name(s)]
OS? (Adequate user-rights?) [Windows-version?]
Any memory-resident program? [like virus-protection?]
Additional question:
are the skins-files shown with a BSPlayer-related icon?