[PROBLEM] How to successfully update 1.0a3 to latest release?

[mixpc]

Hello,

My current Xbian install is 1.0a3, XBMC 12.0RC1, no overclocking, right power supply, 1 usb device connected hosting three .avi files, LAN-connected RPi, 2GB SD card.

Terminal

XBian 1.0a3
──────────────────────────────────────────────────────────────────────────────

┌─────────────────────── Config > Packages ──────────────────────────┐
│ │
│ # Package Installed Current Available │
│ ┌────────────────────────────────────────────────────────────────┐ │
│ │1 Config-Shell [ No ] [ ] [ 2.0 ] │ │
│ │2 Config-Xbmc [ No ] [ ] [ 1.0 ] │ │
│ │3 Couchpotato [ No ] [ ] [ 1.0 ] │ │
│ │4 Development [ No ] [ ] [ 1.0 ] │ │
│ │5 Download [ No ] [ ] [ 2.0 ] │ │
│ │6 Firmware [ No ] [ ] [ 1.3 ] │ │
│ │7 Headphones [ No ] [ ] [ 1.0 ] │ │
│ │8 Kernel3.6.11 [ Yes ] [ 1.1 ] [ 1.2 ] │ │
│ │9 Lirc [ Yes ] [ 1.3 ] [ 1.3 ] │ │
│ │10 Nzbget [ No ] [ ] [ 1.0 ] │ │
│ │11 Samba [ No ] [ ] [ 1.0 ] │ │
│ │12 Sickbeard [ No ] [ ] [ 1.1 ] │ │
│ │13 Transmission [ No ] [ ] [ 1.0 ] │ │
│ │14 Webserver [ No ] [ ] [ 1.0 ] │ │
│ │15 Xbmc [ Yes ] [ 1.4 ] [ 2.1 ] │ │
│ └────────────────────────────────────────────────────────100%────┘ │
├────────────────────────────────────────────────────────────────────┤
│ <Install/Upgrade> < Return > │
└────────────────────────────────────────────────────────────────────┘

I've tried to update it by following the alternative method without success even on the first step:
sudo apt-get update

Terminal

xbian@xbian:~# sudo apt-get update
[sudo] password for xbian:
Ign http://aptmirror.no-ip.org wheezy InRelease
Err http://aptmirror.no-ip.org wheezy Release.gpg
Something wicked happened resolving 'aptmirror.no-ip.org:http' (-5 - No address associated with hostname)
Hit http://apt.xbian.org wheezy InRelease
Hit http://mirrordirector.raspbian.org wheezy InRelease
Ign http://xbianmirror.thuisserver.com wheezy InRelease
Hit http://xbian.brantje.com wheezy InRelease
Ign http://xbian.dehakkelaar.nl wheezy InRelease
Ign http://aptmirror.no-ip.org wheezy Release
Hit http://archive.raspberrypi.org wheezy InRelease
Hit http://xbian.dehakkelaar.nl wheezy Release.gpg
Hit http://xbianmirror.thuisserver.com wheezy Release.gpg
Hit http://xbian.dehakkelaar.nl wheezy Release
Hit http://apt.xbian.org wheezy/main armhf Packages
Hit http://xbianmirror.thuisserver.com wheezy Release
Hit http://mirrordirector.raspbian.org wheezy/main armhf Packages
Hit http://mirrordirector.raspbian.org wheezy/contrib armhf Packages
Hit http://mirrordirector.raspbian.org wheezy/non-free armhf Packages
Hit http://mirrordirector.raspbian.org wheezy/rpi armhf Packages
Err http://aptmirror.no-ip.org wheezy/main armhf Packages
Something wicked happened resolving 'aptmirror.no-ip.org:http' (-5 - No address associated with hostname)
Err http://aptmirror.no-ip.org wheezy/main Translation-en
Something wicked happened resolving 'aptmirror.no-ip.org:http' (-5 - No address associated with hostname)
Ign http://apt.xbian.org wheezy/main Translation-en
Hit http://xbian.brantje.com wheezy/main armhf Packages
Ign http://mirrordirector.raspbian.org wheezy/contrib Translation-en
Ign http://mirrordirector.raspbian.org wheezy/main Translation-en
Ign http://mirrordirector.raspbian.org wheezy/non-free Translation-en
Hit http://archive.raspberrypi.org wheezy/main armhf Packages
Ign http://mirrordirector.raspbian.org wheezy/rpi Translation-en
Hit http://xbian.dehakkelaar.nl wheezy/main armhf Packages
Ign http://xbian.brantje.com wheezy/main Translation-en
Ign http://archive.raspberrypi.org wheezy/main Translation-en
Ign http://xbian.dehakkelaar.nl wheezy/main Translation-en
Hit http://xbianmirror.thuisserver.com wheezy/main armhf Packages
Ign http://xbianmirror.thuisserver.com wheezy/main Translation-en
Err http://dikonist.asuscomm.com wheezy InRelease

Err http://dikonist.asuscomm.com wheezy Release.gpg
Unable to connect to dikonist.asuscomm.com:81:
Reading package lists... Done
W: Failed to fetch http://dikonist.asuscomm.com:81/dists/wheezy/InRelease

W: Failed to fetch http://aptmirror.no-ip.org/dists/wheezy/Release.gpg Something wicked happened resolving 'aptmirror.no-ip.org:http' (-5 - No address associated with hostname)

W: Failed to fetch http://aptmirror.no-ip.org/dists/wheezy/main/binary-armhf/Packages Something wicked happened resolving 'aptmirror.no-ip.org:http' (-5 - No address associated with hostname)

W: Failed to fetch http://aptmirror.no-ip.org/dists/wheezy/main/i18n/Translation-en Something wicked happened resolving 'aptmirror.no-ip.org:http' (-5 - No address associated with hostname)

W: Failed to fetch http://dikonist.asuscomm.com:81/dists/wheezy/Release.gpg Unable to connect to dikonist.asuscomm.com:81:

W: Some index files failed to download. They have been ignored, or old ones used instead.

I should note Internet connection works ok. I've also tried updating through SSH and then updating packages

Kernel3.6.11
Lirc
Xbmc

but even though a message says they've been updated, rebooing Xbian and checking that info both through SSH and the XBMC Settings info shows no such an update has taken place.

So could anyone give me some advice on how to update my Xbian install to the latest release 1.0 Alpha 5 and/or latest packages? They only thing I want is losing all the addons and settings I've set up so far. That's why I've made use of the XBMC Backup addon.

Thanks in advance!