WordPress.org

On WordPress v2.7 and later, the installation is as follows:

1. Go to the 'Plugins' / 'Add new' menu
2. Upload wordpress-mobile-pack.zip then press 'Install now'.
3. Activate the switcher plugin. Change its settings as required.
4. Select which desktop widgets are to appear on the mobile theme.
5. Enjoy.

On WordPress v2.5 and v2.6, the installation is very slightly different:

1. Locate your WordPress install on the file system
2. Extract the contents of wordpress-mobile-pack.zip into wp-content/plugins
3. Activate the switcher plugin. Change its settings as required.
4. Select which desktop widgets are to appear on the mobile theme.
5. Enjoy.

The Mobile Pack also uses a cache directory to improve performance, make sure the Web server has write permissions. The cache directory is, from the root of your WordPress install, in wp-content/plugins/wordpress-mobile-pack/plugins/wpmp_transcoder/c.

Also, to complete the installation, the web server needs to have write permissions to the themes directory in wp-content/themes.

The Pack comes with complete documentation in HTML format that you can read on your browser. Some of the most common permission issues are covered there.