I figured out why mine wasn't showing up. I was having the same problem as you. You need to:
- Make sure you have the anchor text ("homework file") placed in-between your short code like this: [wplms_s3 duration='10' link='filmschool/12/Assignment.pdf']homework file[/wplms_s3]
This worked for me. There needs to be some instructions for this with a hove link in the upload section. My customers aren't going to know how to do this! This is going to be frustrating to support! You should make the file name be automatically included in the shortcode. That would be helpful.