In order to create a new board outline:
1.) In the Select toolbox de-select all icons except for the last one (Enable Selecting Other Objects)
2.) In the design toolbox select the "Board Outline" layer
3.) Select the outline (the default rectangle) and press the delete button.
You now how three ways in which to create the board
1.) Manually: Go to Place >> Shape or Place >> Line to create the board
2.) Automated: The board wizard at Tools >> Board Wizard
3.) Import a DXF: File >> Import >> DXF
There is however no way of scoring the board.