Strange electrical problem, ESC, gauge pointers, cruise control etc.

Hey everybody! I've had a small electrical problem in my Cruze since last winter and I was wondering if anyone had an idea where to look for solution!

Here's a video of the problem:

In a nutshell, I get some false alarms on the dash every now and then:
-ESC warning lights up permanently with an audible beep, disappears after restarting the car.
-Gauge pointers drop to zero for a fraction of a second.
-Reversing sensor warning light blinks once or twice.
-If the cruise control is engaged, it shuts down (back to grey light from green) and the CC memory is cleared.

The problem occurs only when weather is cold and very damp. Not tied to any specific appliance, the engine temperature has no effect on this, nor the speed, rpm range or gear selected. I have already had the negative batt cable (95281536) replaced, but no help. Been to service twice over this issue, the official dealership wasn't keen on investigating and the other garage just started with the basics. I'm pretty sure this is just a loose connection or bad cable somewhere, just don't know where...

Oh, and my Cruze is 2012 model, 2-litre 163hp diesel with automatic transmission and LTZ trim level. It now has 122.000km on the clock, that's about 76.000 miles, right? My car no longer has factory warranty active, here it ends after 100.000km.

Thanks in advance!

Cheers
Oxalainen
Finland

And for the record, I still love my Cruze, despite this minor issue.