I don't want to sound like I am nagging you, but I will request this one more time. Please say yes or no and I'll stop bothering you.
On the Edit Titlebar Buttons dialog, when the user selects a HotKey, it would look very polished if the TitleBar Button dropdown wold auto-select the default image for that hot key. This would be very user friendly. I not sure offhand if this would be an CBN_SELENDOK or CBN_EDITUPDATE notification message, or what, but it ought to be an easy to add the behavior.
Don't worry, you're not bugging me. This feature is coming in Beta 8. I haven't added it until now because I didn't have a way of determining which image is the correct one. There are 18 images, each in 3 different colours. So first I had to have a system that can determine which colour to use (that is in Beta 7 and being used for something else). Now that the foundation is there you can expect the auto-selection in Beta 8.