Hi Klaus,
here's a simple code to show there's a bug with events.onmousewheel that does'nt work in the above conditions:
Code
<krpano onstart="set(events.onmousewheel, mousescrollequi);">
<area mode="border" left="30%" />
<action name="mousescrollequi">
add(layer[scrollarea].y, calc( 5 * wheeldelta ));
</action>
<layer name="scrollarea" parent="STAGE" type="container" bgcolor="0xFF0000" bgalpha="1" align="lefttop" width="200" height="2000" y="0" />
</krpano>