Using TEX in Mathtype

I use Mathtypeto insert mathematical equations in MS world.
Today I understood that there's no built-in symbol for $\mathscr(F)$ in MathType so I searched for a way of using LaTex codes in MathType. here and here and on this page, it says that it's possible for MathType 6 users and later to use $TEX$ in MathType editor.
But whenever I try, I see that TEX codes won't be translated and nothing happens. The version of MathType installed on my windows 7x64 is 6.9a. Is there anything that I should do?

p.s.
I have MiKTeX 2.9, Texmaker and Word-to-LaTeX installed on my computer.