Hi ollie.ha,
If you look at the top left of the form Home Screen you will see red circle with Steinberg also in red, tap on the circle and select Steinberg Lounge, there you can upload your creations.
Mike
I have four tracks uploaded there so far, three of them are my own electronic compositions, the forth is a cover of a well known Jean Michel Jarre track.
Here is my cheeky link: