cannot add a theme to Adobe PE 7 InstantMovie

[irispix]

I read in the PE 7 user guide that to add a theme to my instant movie, I have to select it from the thumbnail, click the Play button to watch a preview and then Click 'Next'.
'Next' is not highlighted and when I click on it nothing happens.
Is it disabled? What do I have to do to enable it?

p.s. I am new to video editor programs. I am starting from the very basic.

[Paul LS]

Firstly you need to select the assets for your instant Movie.. you can do this in the Organise panel... CTRL click all the assets you want in the movie then click Next. Then select your Theme and you should be able to select Next to move to the apply stage. If this is not happening can you describe all the steps you are taking.