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.
The plug removal is tough. The endcap/plate that holds the spring and plug in the mag tube has two little wings or studs that hold it in the tube. You have to push one side down into the tube and rotate it so the tabs are orientated up and down. That way the narrow sides will fit out through the end of the mag tube. I used needle nosed pliers but you might want to wrap them in some tape as they will scar the endcap
This isn't shown in the manual (it's pretty basic, generic to all Derya shotguns, and is mostly pictures) I got the "how to" info by calling O'Dell. O'Dell Engineering is the importer so they may be able to help with a manual.