create an icon using a plugin to make the transition. maybe use a light switch image. if that plugin was called 'switch' you could try this. create 2 actions lights on and lightsoff.
<action name="lightson">
loadpano(lightson.xml,null,KEEPALL,BLEND(2)); set(plugin[switch].rotate,180);
</action>
<action name="lightsoff">
loadpano(lightsoff.xml,null,KEEPALL,BLEND(2)); set(plugin[switch].rotate,0);
</action>
<plugin name="switch"
url="switch.jpg"
keep="true"
visible="true" enabled="true" handcursor="true"
zorder="5"
alpha="1.00" blendmode="normal"
smoothing="true"
origin="centerbottom" edge=""
x="0" y="10"
scale="1"
onclick="switch(lightson(), lightsoff());
/>
that command will load the new lights on image keeping all viewing and display settings over 2 seconds. it will also rotate the switch icon 180 degrees so it looks like the switch was actually flipped. the next time it is clicked it will reverse the actions. if 'set' does not work on the rotate try 'tween'