I ask as the novice OpenLP volunteer who has the machine at the moment claims an edited song takes "20+ seconds to refresh when saved" and is getting variable results with an .mp4 file, not reliably starting when selected as the next service item and the same sort of problem with a .pptx file.
I'm not clear about the source of the .mp4 file, but but the video is available on YouTube. I understand the .pptx file was generated on a Mac, so the issues might be related to the external files rather than OpenLP (Windows) itself.
I'll have a chance to play with the laptop in a week or so and may discover more that will help resolve the issues.