Просто нашел, как исправить это в Natty. Добавьте строку:
dashView.dashMode = DashDeclarativeView.FullScreenMode
в функции activateHome (). Например:
function activateHome() {
pageLoader.source = "Home.qml"
/* Take advantage of the fact that the loaded qml is local and setting
the source loads it immediately making pageLoader.item valid */
activatePage(pageLoader.item)
pageLoader.item.shortcutsActive = true
dashView.activePlaceEntry = ""
dashView.dashMode = DashDeclarativeView.FullScreenMode // ADD THIS LINE
}