Some friends said that they can't change their username. Actually,you can reset it in the main page:click my wallpaper and there is a blank space which have a “name”tip ,you can reset your name overthere.
Now, you can choose whether or not to hide the text and time, or even the leaves special effects. → Find out the properties bar, and click on the bool box with "Greeting"/"Time"/"Leaves", then, work done!