Close google chrome
Open the theme folder
Locate Cached Theme.pak
Right click Cached Theme.pak and select delete
Now start chrome then go to the chrome://extensions/
Check the developer mode check box to enable developer mode.
Select load unpacked extension and browser for the themes folder.
select the folder called HUD Chrome Theme and click ok


Note: the manifest.json must be in the root of the selected folder so if your selecting for example (my themes\HUD Chrome Theme) and your selecting my themes as the folder it will not be able to locate the manifest.json but if you select the HUD Chrome Theme because the manifest.json is in the root of this folder it will then load the extension.

Also note: that in order for the animated background the theme must not be packed in to a .crx as it needs to exploit a bug in chrome allowing you to use .gif files in an unpacked theme.