I experience a similar problem in Poser Pro.

When using the drop down menu to select library items there are occasionally entries that are greyed out and consequently unselectable.

However, when using the icons instead, I can select all my library items, regardless of whether or not they were greyed out in the drop down menu.

An example of a grey out menu item is attached. The hair folder is greyed out. Which ones, if any, are greyed out varies with each program launch.

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