saving to a DVD in Video studio pro x 6

I am trying to save to a DVD-R in video studio pro x 6 and have got to a point where I can't go any further. When I get to the point where I click on CREATE DISC it doesn't come up with the option to click on NEXT. Nothing I seem to do will get the NEXT button to highlight. I have tried following instructions from pro x 5 which I used to have but it still won't do it. I have tried going into setting and options and then into preferences and have made sure that I have selected where I am saving to i.e. E drive and still the NEXT button will not highlight. The DVD has a capacity for 4.7 and the project is 2.43 so it should fit on the disc. Does anyone have any other suggestions that I can try please.