Tweak and fit module not properly installed? newbie

[quasimodo1]

Hello, I have bought and downloaded MF4 and so far so good. However when I want to burn a larger file onto a DVD I need to use the "Tweak and fit" option.

My problen is when I want to do that I get the following message:

"Tweak and fit module not properly installed" Please could anyone help?

Thank you for taking the time to read this. Mike Tagg