TV dropdown menu input type difference

In Evo I use something like this as the input type of
a dropdown menu in a TV:

Grid...==||Yes==showgrid||No==nogrid

When displayed in the document it will show "Grid..." and
by clikcing you can select yes or no.

I use this TV as a class in my markup and in Evo it use to
place "showgrid" if you choose "Yes", "nogrid" if you choose "No",
and "nothing" if you leave "Grid...".

Now in Revo, it show "Grid..." when you leave the "Grid..." option...
How do I fix this?