I have a movie on a DVD disk which contains some sections that I want to add to a movie project which now contains only slides. The movie was improted to the timeline of the project but the video did not appear (only a black screen). A red line above the added movie indicated that it needed rendering. After 2 plus days the green line above the added movie finally appeared. Now instead of a black screen there is a blur.
There are a lot of variables. I think I might try "ripping" the DVD footage to a more typical MP4 file before importing it to the timeline. Getting the project setting to match what you want for output and mixing it the stills may take some trials.