@ Charles Kenyon : I've updated my profile...although I still use Office 2003 with Windows 7 at home. But actually, my main concerns are with Office 365 for Mac

@ Moonshine : thanks. Unfortunately it seems I won't be able to do what I want to do.
The link confirms what I had experienced : MS reduced to 125 commands only what you can add to the QAT... And I think no simple macro can just do what I want : display a dropdown menu to let me choose the font color...
Office 2003 is the best version for my own use : simply and highly customizable.