Poor casting, uncooperative "actors" can wreck a movie.
Ensure the "actors" are willing to help out and don’t waste the valuable video process by mucking around and wasting the lessons.
Any issues, see me, as this a serious part of your work and must work well, to succeed.
That does not mean don't have fun, but it's still, a lesson!
Your "actors" must read their parts in the script and as importantly must understand the plot (what the video is all about. and as importantly want to be a part of your successful video.