Accenta 8 mini - light constantly flashing after another switch tripped?

Have not used my alarm for 3 years due to motion sensors and cats not being compatible. After another electrical fault/surge or blown fuse yesterday, resetting the RCD switch on my fuse box set the alarm off. This was a bit of a surprise as I thought that the whole system had been disabled by the electrician some time ago. Managed to get the sounder off by flicking RCD switch off and on again but exterior light won't stop flashing. The panel won't accept the code and seems to have stopped working completely now since flicking RCD switch off and on again...no sound made when code entered and no power light on keypad. Motion sensors are working again when had been dormant.
Any quick fixes before I call an engineer, given it's sunday?! Thanks.

Kitty