UINT BCGM_ON_RIBBON_CUSTOMIZE

The message is sent to parent frame when user begins customization.

Parameters

wParam	this parameter is not used.
lParam	a pointer to ribbon control to be customized.

Returns

application should return nonzero if it processes this message and displays its own customization dialog. Otherwise the library will display built-in customization dialog.

You should process this message if you wish to display your own customization dialog.