Im trying to learn Karma by just doing the most barebones example in Solaris. But I cannot figure out why "Render to Disk" are always empty files. Can someone take a look at this basic failed example and point out what I am missing.

Thank you. Much appreciated.

There is nothing wrong with your scene, it renders fine on my system.
Try changing the output picture path to something like your desktop so you can easily locate the final output.

Maybe Karma is not compatible with my Mac.

I ran into the same issue. It must be a bug. I try disabling denoising and it didn't help.