Unable to download or upload files through dropbox ( using their API )

Question

I have registered and been approved, created my application and made a key/secret. I'm using the dropbox-php and I'm unable to download/retrieve files but I am able to access metadata info.

I have tagged my application as 'sandbox' and not metadata info. I am able to access the metadata info fine:

$dropbox = new Dropbox_API( KEY, SECRET, null, 'dropbox' );
$info = $dropbox->getMetaData('/', false );
print_r($info); // WORKS AS EXPECTED

The issue is with the getFile method:

$fetch = $dropbox->getFile( '/what.txt' );

Gives me:

Uncaught exception 'OAuthException' with message 'Invalid auth/bad request (got a 403, expected HTTP/1.1 20X or a redirect)

By the way I am using the OAuth extension.