Adding photos to imovie project

Hi - I may have posted this on the wrong discussion previously. If any one can help me solve this problem Great!

Im a little confused and frustrated. I prepared a photo slideshow in imovie and I also have selected video clips in imovie which I want to intersperse with this slideshow so it becomes a combined slide & video show. So I may start with three or four slides, switch to a video clip then back to slides for a while then insert a further clip and so on. Is this possible and how do I do it? Ive trawled through a bunch of google how to's and apple community answers but there doesnt seem to be any easy answer except go back to iphoto and import from there which becomes tedious having done it all before. I would also like to keep the inserted maps that I made for the slide show. Any help is greatly appreciated

iMac, Mac OS X (10.7.5)