When you edit a line you have the opportunity to change the name of the line, and also whose line it is.
The Line editing screen appears as below with the current line name shown in the name field.
You can select a new character for the line just by pressing one of the characters shown, though if you are moving all of a persons lines to another person it can be done in one go on the Characters screen.TOP TIP: If you want to easily rename a line and have an iPhone 4s or iPad 3 or later use the microphone button on your keyboard. Then just say the start of the line and it will put it in the name.
When you click on the stage direction it gives you a large text area where you can enter any stage direction notes you wish to make. The tip for the lines also works well for stage direction.