Sleep up is using binaural beats. More information here. Hate to break it to you but you paid for something that is free. The only thing you bought is a “fancy” way of doing it. 
For those of you who don’t want to buy the app but can have a computer open while you sleep download Brainwave Generator. It comes in the Goods folder on some lucid software sites. 
It will take minor configuration and if you’re too lazy to figure out how to configure the BWGen, send me a PM and if you have your e-mail as public I’ll mail you the file you need to play. 
And if anyone out there wants to help make the file that you need to play more public, contact me in a PM with a method that will work, i. e. Megaupload or something and I’ll may you the file to, I’m just to lazy to do it myself. 
Edit: Ha! Sometime after I wrote this I found a topic in the Knowledge base all about it! Their method is almost a perfect copy of what I did. 
Well here’s the link. Brainwave Generator -LD4ALL Site