How Create/Add Custom imageMSO Icons to MSProject via VBA

Hi Forum!
I wish to create custom icons for MS Project 2016 to add to my custom tabs.
In MS Project 2016, I created XML in a VBA that automatically creates custom tabs via the "Auto_Open" named macro. That works perfectly. However, I can only use standard imageMso icons. I wish to create new, custom icon images.
In the past, I have used the CustomUIEditor.exe to insert icons for Excel, yet this does not work for MS Project. From what I see, that tool is good for Excel, Word and PowerPoint only.
From my internet search, I have not identified a method/way to create, store and add custom icon images to an MS Project custom tab. Thus far, I am OK at writing VBA macros, creating custom tabs, and using standard imageMso icons. Yet, I am not a "trained" MS Developer in VBA or XML and could use an assist in this area.
Many thanks in advance!
Allen