While you are on the site, in your browser find and click "Add to Home Screen" A CGN beaver app icon will then be created to your phone that is directly link to the site.
Note: This feature may not be available in some browsers.
I know it's for the 552 and not the Black Special but there is a great deal of similarity. I could have sworn that I downloaded the Black Special manual from them but for some reason there's no link to it anymore.
With the folding stock just give it a good hard pull to open it back up. You won't hurt anything. It only locks in place with the stock in the normal position.