Windrose and variables

Hi,

The windrose looks nice, and I am able to display data in it from postgresql.
To advance a bit I introduced variables (for the different weather stations I am displaying)
I have a muliple choice enabled and the windrose replicates when several weather stations are selected. It all works fine EXCEPT that rose number one never changes what it shows. It allways displays the same rose no matter which weather stations I select from the dropdown variables list.

Any clues on how to fix this?

Thanks
Helge