Customization of Command Controls in the GUI was possible outside of
programmatically creating it in the earlier versions through simply the
View/Toolbars/Customize. You could go to Macros and manually enter a
function that was created in an add-in that doesn't appear in the list.
Apparently it still doesn't appear in the list in the BETA, so it would be
great to have the capability to manually enter the macro/function there and
assign it a control. Shouldn't be hard to implement in the new ribbon UI
considering XML standards.

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