When you first add a board you can define the number of phases and circuits for the board. Once added the way to add or delete circuits is described below:
Click the green + button to add an extra circuit until you reach the desired number
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To delete a circuit, click the circuit as shown below so that it is highlighted in pink and click the bin at the end of the row
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After you have clicked the bin you will see a warning asking you to confirm your selection
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