Without the .capx it's hard to say but a few suggestions:
Are you certain you are using the Button Objects's conditions to test for click?
Have you imported the video file?
Have you put the exact video file name in the correct source field for the Video plugin?
e.g. if the video is a webm video entitled 'myway.webm' then that should be the exact file name you should use, no quotes, in the webm source field.