Originally Posted by birdy

Open your saved folder outside of LW (go to LW library, click on Saved Files, click Explore)... now your saved folder's open.
Right click on a file of the type that you want WMP to play (eg music file, video file) > open with > choose program. Now choose WMP. Tick the box that says "always use the selected program to open this kind of file". Now click "ok".

That's it