The program does not play

Hello, I have a problem with superlab. I’m trying to do a study on temporal perception. To do this, I created a file in superlab that contains several uploaded videos. First, participants have to read the instructions, and then they have to press the “space” key to begin the study. However, there is a text box in the instructions and when participants touch the “space” key, instead of the program skipping the instructions, it starts writing in the text box and does not move on to the next steps.
Another problem is when I try to play the videos. The screen goes black when a video starts and it is not possible to view its image. When the video is finished, the participant must give an answer about how long they think the video lasted and a text box is presented to that effect. However, after the video presentation (where it is not possible to view the image) the text box appears, but disappears very quickly, not even giving the participant time to write their answer.
This is the first time I use superlab and I don’t know how to use the platform very well. If anyone can help me, I would really appreciate it.
(I have a computer with Windows 10)
Thanks!