I've searched for an answer, and found nothing. The best I discovered was an old thread from 2007, where people said it couldn't be done. Now, that was 7 years and 2 generations ago, so I'm hoping maybe something has changed!
Is there a way to get a custom image on the stock Nav screen? Either a background image, or at least an image that displays at startup. I know the entire infotainment system is essentially worthless... but it would be great to be able to customize it a little!
If it can't be done, I suppose I'll just have to wait until I get a decent aftermarket unit in there (plus a conversion to a lesser-CTS console to retain the useful info that the Nav unit currently displays.)