Refit your original control board.
The most likely cause of this problem is the water indicator.
Take out the bottom basket, take out the filters and look into the sump.
There should be black grid on the right side of the sump.
Clean this out, pour a kettle of boiling water into the sump getting as much as possible into this grid.
Immediately reset the dishwasher and start it on it's hottest wash.
If this doesn't sort it you you'll have to replace the water indicator.
Hope this helps
Let me know how it goes or if you need more help.
It doesn't take much for the water indicator to not work. It's one of the most common faults on these dishwashers.
It's not uncommon for the machine to misreport the fault. It seems more likely to happen on the updated software, hence the reason I suggested putting the original board back in.
I've also come across machines where the new board won't work but the old one does (once the actual fault is cleared).
The machine detects a leak if the water indicator reports a loss of water during use.
It will also report a leak if the water is known to be coming in (flow meter sends impulses) yet the water indicator doesn't send a signal to say 2 litres have entered.
If the drain hose is into a stand pipe, ensure the hose isn't too far down the pipe causing the water to syphon out as quickly as it comes in.
If the boiling water trick doesn't work, I'd suggest replacing the water indicator on a "fit and see what happens" basis. Unfortunately parts aren't inexpensive but this is one occassion I'd suggest risking the money.
Let me know how it goes.