Video playback and Construct 3

Please can I have an understanding of video playback in Construct 3. Does this work seamlessly, or are there known problems. We are trying to implement a video. On one machine I can not get it working in the editor. Nothing plays at all. When I render it to win64 I can get it playing but no sound. On another machine we can get it working but it always only plays the top left corner of the video. Are there video libraries we should have installed, are there known issues. Really struggling here. Have tried both auto play and play on click. results the same. Thoughts really welcome.

I use video and it works great! I use it through nwjs and pick a video file on my local computer.

I used ".webm" files for video, as this has the highest compatibility.

Firstly thanks so much for taking the time to answer. Jase00 did you need to load any divX libraries or the like? Did you have any settings that you had to put in? Do you have a sample project that is working we could have a look at? Just do not understand why ours does not work, and we have tried it on two laptops. We just seem to be missing something.