Can't start vauxhall adam

[lecky4]

Hi all, sorry for posting in the general disscusion, but I can't see a forum for the Vauxhall Adam.
My daughter was out and the car running as normal, but after she'd been parked up for an hour or so she went to start it to go home and it wouldn't start. By the time the breakdown/recovery (RAC) showed up the electrics were completely dead, no dashboard, nothing. RAC man measured the battery voltage at 5V, but got it started and advised a new battery. So she brought it around to me. She bought a new battery and as per the owners manual I turn the ignition on, then off and disconnected the battery within 15 seconds. Replaced the battery and it started first go. The only problem was the distribution box on top of the battery didn't fit properly because of the battery handle, so next day when I went to start it and take it to hers all the electrics were dead, I wasn't to concerned, figuring it was because of bad connection due to the distribution box. So out with the battery, charge it, remove the handle and fit the distribution box, perfect. Fit it back in the car and she starts first time. Unfortunately this morning when I go to take it back the fob opens the doors, dashboard lights as normal, depress the clutch, turn the key to start and all the electrics die. Completely dead, nothing, not even able to lock or unlock the doors with the fob. Has anyone got any ideas what the problem may be? I can't find any tips anywhere.