You will find the main PSD file at resources/storm.psd in the downloaded package. This PSD has the design for the main pages and elements. Each page / section is in its own folder and may be hidden.
Find the folder in the layers panel that is named after the page and click eye icon. Every element is grouped neatly in their own folders. Hidden elements are in orange layers.
If you are looking for something specific and you cannot find it in the main Photoshop file then please contact us.