Thumbnails for stock content has nothing to do with CITP. The images are defined in the library.
Once you start the CITP process and it's almost complete the Library Defined thumbnails will disappear and be replaced with the CITP thumbnails along with the custom content thumbnails.
Are you seeing the spinning arrows in the Media Picker window?
Thumbnails for stock content has nothing to do with CITP. The images are defined in the library.
Once you start the CITP process and it's almost complete the Library Defined thumbnails will disappear and be replaced with the CITP thumbnails along with the custom content thumbnails.
Are you seeing the spinning arrows in the Media Picker window?