Form Height Not Resizable

Becouse this option on desktop version is "blocked"?
At mobile version of b4p this change at "real" height of desktop mobile (samsung omnia have 240x348), but on desktop version is not possibile change this value? For QVGA PPC?

And "next" button is blocked? Becouse non change at click on "next"? xD
:sign0085:

In the designer you can choose Tools - Screen size and change the size of all forms.