  $\gamma (p,K^0)\Sigma^+$ cross section was measured at the CBELSA/TAPS
experiment at the ELSA electron stretcher facility. A cusp-like structure was
apparent near the $K^*$ production threshold, where the cross section reduced
by a factor of four in the forward direction. It is speculated that t-channel
$K^*$ exchange, and meson-hyperon dynamically generated states may have large
contributions to the cross section. The motivation for the extraction of the
beam-target double polarisation observable, $E$, is discussed, and the new
experiment, BGO-OD at the ELSA facility is introduced.
