To achieve this your meCoffee needs permanent power, the boiler needs permanent NEUTRAL and your meCoffee needs to be aware of the state of the power button.
First move the red & green wires powering your meCoffee at the power button from the upper switched terminals to the corresponding lower permanent terminals.
Now move the switched NEUTRAL(black, upper left) wire to the corresponding permanent(lower left) terminal using the short green wire from the set.
Finally use the black wire from the set to connect the switched LIVE terminal of the power button(upper right) to terminal #8 of your meCoffee.
To prevent your machine heating up when plugging in the mains or in case of a power failure, go to the timer settings in meBarista and check Installed as a timer. This will prevent the machine from heating up on a cold boot.