Please hit the Reply button not the new thread button when replying. Else your post will be deleted for subsequent replies.

This will happen for any software you're using. I think your mistake is you're previewing songs & videos right? Yes you can only preview as much as you've downlded. If you've only downlded 10% of a song then you're only going to be able to listen to 10% of it which might be 20 seconds for example. To listen to the whole song or video wait until it's 100% downlded. You'll find the completed downlds in your Saved files folder in the LW Library window. Select that folder & the file & press Launch button. Else move it out of the folder & open it with your normal player.

Also, if your files are showing corrupt you can go to LW's menu Tools>Options>View>Popups & press revert to default & press apply button.