Well, let's see if i have this correct.
You have a completely blank/Empty/plain form in design mode that you want to preview?
If I am correct, then my first question is; Why would you want to look at a form that is completely blank in Design and Preview?
To explain, the design mode, bizarrely, is where you make changes to the form from a functional point of view or design it. The preview is where you act as a user of the form to iron out bugs etc.
This may just be a common sense thing that says you cannot preview a blank form as there is nothing to preview.
I hope this helps
Adam
PS if you want it to work at the word TEST somewhere on the screen in design mode.