@sjuro54. Thanks for explaining what you are experiencing.
OK, I have to say that between 3.3.3 and 3.3.6, there is no change to how links to files are handled, whether for download or preview. I think it has been a while since I made any changes to that. So, whatever you were doing in 3.3.3 should work in 3.3.6. I am surprised you would say that what you were doing does not work any more.
As for streaming, or playing video and audio files, I could definitely try to add it in future releases. Most of what Easy Folder Listing Pro has become came about as a result of customer requests and suggestions.
In terms of what you said about changing mp4 and mov to mp3 for playback. Easy Folder Listing Pro does not render any media really. It is your browser that renders it, based on the file type. As I think about it more is that what may be happening with you changing extensions is due to what I have allowed the native previewer to preview. Currently, the native previewer allows previewing (technically, I guess it could be called ‘streaming’ or ‘viewing/playing’) of files with the following extension: pdf,gif,png,jpeg,jpg,bmp,mp3. Basically, the native previewer allows your browser to handle those file extensions.
If you a familiar with editing code, I could tell you where and what to edit to add mp4 and mov. If you are interested, let me know. If it works out the way you need, I will add it to the next release and maybe try to improve it.