KB: Default grid unit and Comment/Designator visibility in Schlib

Solution Details

To change the document options while editing a symbol within a schematic library, go to Tools » Document Options, which will open the Properties panel.

The unit settings and the Comment/Designator visibility can then be changed under the 'General' section of the panel.
 

Here's a link to the relevant section of documentation on the Properties panel with more detailed information on the settings available in this panel:
Schematic Library Support