It's not a bug, you must set the panel on top with BringToFront in the designer in the Tools menu.
The last generated Views are on top of the display hierarchy.
You probably set the Panel first and the other views afterwards.
In your example you'll need something to set the panel invisible.
It would be intersting to have a method to set 'BringToFront' by code.
Sub Globals
Dim Button1 As Button
Dim Button2 As Button
End Sub
Sub Activity_Create(FirstTime As Boolean)
Activity.LoadLayout("1")
BringToFront(Button1)
End Sub
Sub BringToFront (v As View)
For i = 0 To Activity.NumberOfViews - 1
If activity.GetView(i) = v Then
activity.RemoveViewAt(i)
activity.AddView(v, v.Left, v.Top, v.Width, v.Height)
Exit
End If
Next
End Sub