Hi,
Thanks for notice that you can't add records. It's permission issue and I've fixed this and published new version in the store.
If you didn't change any permissions for "Address" recordset in RecordBrowser admin panel, then it should fix your problem to add new address.
"get" function is just a method accessible for other modules to obtain addresses list for certain record.
If you wonder how it's done, that you have another tab under contact/company record called "Addresses", then you should know what addon is, and how it's used.
In install file we defined a new addon for contact/company:
Utils_RecordBrowserCommon::new_addon('contact', 'Premium/MultipleAddresses', 'body', _M('Addresses'));
Utils_RecordBrowserCommon::new_addon('company', 'Premium/MultipleAddresses', 'body', _M('Addresses'));
where "body" method of MultipleAddresses_0.php is called to show list of addresses.
Regards,
Adam