Evidently the default purpy desktop graphics didn't make it into the beta. :( You can find the purpy wallpaper here (among all the others):

https://git.devuan.org/devuan-packages/desktop-base/tree/master/backgrounds

And it looks like the purpy window manager theme is here:

https://git.devuan.org/devuan-packages/clearlooks-phenix-purpy-theme/tree/master

Put the following elements into a directory named Clearlooks-Phenix-purpy:

index.theme
gtk-3.0
gtk-2.0
openbox-3
metacity-1
xfwm4

Then put that directory in /usr/share/themes/ .

You will also need to change two settings in Xfce:

1. Menu > Settings > Appearance > Clearlooks-Phenix-purpy

2. Menu > Settings > Window Manager > Clearlooks-Phenix-purpy

Hopefully all this will be integrated by beta2.

Enjoy the purpiness!

golinux