If this template helps then use it. If not then just delete and start from scratch.
OS (e.g. Win10): Win10
PsychoPy version (e.g. 1.84.x): 2020.2.10
Standard Standalone? (y/n) If not then what?:y
What are you trying to achieve?: displaying multiple movies, 3 blocks of 5 clips. each clip is about 5 minutes. mp4 files
What did you try to make it work?: I added a movie component in a loop
What specifically went wrong when you tried that?: the experiment runs very slowly. when I press it takes about 10 seconds to load the first introduction slide. when starting each video file, it needs about 5 seconds before it appears on screen and really starts playing.