I test the case of "reading video file in exported folder", it work.
You can try by these steps.
1. download test file (movie.ogg) from gonzdevour's link
http://www.w3schools.com/html5/movie.ogg
2. in capx, assign src url to "movie.ogg", then export capx.
3. put movie.ogg downloaded (at step1) into export folder (at step2)
4. open the index.html in exported folder. It works in my testing.
rexrainbow
I tried these steps but exporting to Node Webkit Desktop export and placed the movie.ogg into the same folder where lies the ".exe". All I get is a black screen. Have you tried this?
I am using the last stable 1.19.