Sometimes I don't want PRE7 to do all the work for me. I may like a particulat theme, and I may think it would work well with my video, but I want to do all the editing.
Her is an example where I wanted to do al the editing, but also wanted a theme applied.
Where my kids go to school (my son is in 1st grade, and my daughter is in 3rd), they put on class music shows once a year. My kids shows are about 20 minutes long each. They can be boring. Applying a theme could add some interest.
I thought that the Performance Star theme would go well with my Son's show, and the Broadway theme for my daighter's show.
I did not want PRE7 to do the editing, so I brought my video to the timeline and I edited it myself. Then I applied the theme. For parameters, I un-checked "auto-edit", chose "entire movie", and selected "no music". For theme content I have all checked.
When the theme is applied, it will not mess up with the editing you have already done. It will add an intro and closing, and supply some transitions and effects, but in such a way as to enhance what you have already edited.
I did find that if your video clips are too liong, it will not supply many effects. So you may just need to cut a clip at some point if you want more effects.