If I use the .emacs config file from Casey then my emacs background is white. And more color things are not correct. Making the current line very hard to see for example.
Also emacs seems to be very unstable for me with his file.
If I go to:
Options > Customise Emacs > Custom Themes
then I get a Emacs Abort Dialog, mostly directly. Sometimes after a few seconds.
I'm under windows 10 with emacs version 24.5.1.
Emacs broken with casey's .emacs file [Mac problem update]
I'm pretty sure Casey uses an older version of emacs, you could try downgrading to it and maybe that would fix it. I faintly recall Casey mentioning something about errors in new versions or something of the sort.
If you're getting an error before the line in the .emacs that sets the color scheme that color scheme will be the default one, which is usually white and other colors.