If there is a folder containing an Animation, it goes in either <OFP>\Addons or <OFP>\Res\Addons - check what it says in the readme. As it comes in the zip, it does not need to be pbo'd.
The Animation is a basically a simple 'mission intro' in a folder in the Addons directory (but this does need to be pointed at from the config of the island); eg.
Addons \ sttabeldes . pbo <--- the island
Addons \ STTAbel_DesertAnim \ <--- the folder for the Animation
Addons \ STTAbel_DesertAnim \ intro . sttabel_desert \ <--- the mission folder for the Animation
Addons \ STTAbel_DesertAnim \ intro . sttabel_desert \ mission .sqm <--- the Animation