If your ball gate works for a period and stops or works once and stops the game is not seeing either the open sensor or the closed sensor for the ball gate.
When the game is first powered on the game will check the state of the closed sensor if sensor is not activated it will turn the motor on to close the ball gate. If the game does not see the closed sensor activate then it will disable the ball gate until the game is power cycled or the programming menu is entered.
When the game is coined up on the first game the board will try to move the gate to the open position if the open sensor is not activated it will disable the ball gate until the game is power cycled or the programming menu is entered.
When the board is trying to detect the sensors the game should not "search" for the sensor by moving back and forth, it should move to the appropriate position and stop. if the game is searching for the sensor this is an indication that the sensor is failing or is not positioned correctly.
The sensors should be mounted flush to the surface of the wood that the ball gate is built on if the sensor has been pushed down it could cause the sensor not to detect the magnet.
When reading sensor signal voltages the signal must go below 1vdc when the magnet is over top the sensor, if this does not occur then the logic will ignore the signal.
Please see the PDF below for more information on the ball gate and the sensors.