With multiple apparently unrelated electrical problems, my thoughts would go towards earth connections, where circuits share an earth, or looking for moisture at the body computer.
Below the windscreen on all cars is a chamber that feeds air into the heater. Air enters and then has to go up inot the heater channel, to discourage the ingestion of leaves and other airborne debris. The chamber has drain holes, to let rain out. On Panda, 500 and Punto, the drain holes have tubes that are 'pinched' at their ends, called duckbills. Their funtion is to allow water out, without letting engine fumes enter the cabin, but their shape collects leaves, which if not cleared turn into compost. The chamber fills with water, and eventually overflows into the cabin. On the models above, this water has a tendency to drop onto the body computer. This is on RHD models.
I don't know where your body computer is, but will be under the dash, probably in front of your left knee. It is part of the in-car fusebox. Have a look and see if it is damp. Careful removal of the connector, and drying out with a hairdryer, on a cool setting, may effect a cure without further expense.
