Hardly. Both those are icons with a transparent background from shell32.dll
painted on the TBitmapImage
using SelectDirPage.Color
and SelectProgramGroupPage.Color
long before any user code is triggered. It cannot be updated. You would have to repeat all the painting code in your Pascal Script. It's probably doable, but lot of work.
The relevant code is in LoadSelectDirAndGroupImages
function:
https://github.com/jrsoftware/issrc/blob/is-6_0_4-2/Projects/Wizard.pas#L752-L781