[Vex C++] Changing a Project Icon

Vex C++

I’ve noticed that there is a folder in the files for VCS named project-icons and inside there are a LOT of icons. How do I change the icon of a project? I tried clicking the drop down arrow next to the name of the project but it is gray and can be selected. Any ideas on how to change the icon?

Any help?
I’ve continued to try, but can’t seem to figure it out.