1) The throne can be used only to capture the king, not the "normal" pieces.
2) Yes, it should be considered as a draw but this site does not support a perpetual check detection yet. What you can do in such situation is to send a message to me and I will set a draw manually.
(gem) Hvis du vil hilse på nogen, på deres eget sprog så prøv vores "spiller ordbog" under "mere om sprog" linket under flagene. (pauloaguia) (vis alle tips)