This is a complete list of steps I went through to configure my N770 in case I have to go through them again. Since I had previously messed the settings up. I am starting with a reflash to the latest version.

I couldn't get these instructions to boot from the MMC to work because the rsync/tar command at the end to clone the installation failed so I will be using my MMC as secondary storage only (e.g. for dictionaries, cached maps, media files etc).

• Upgrade to the latest official version using these instructions. Currently this is 3.2006.49-2. I am not brave enough to try the unsupported OS2007 Hacker Edition yet.

• Tools→ Control Panel → Connectivity , fill in my Home WiFi info. This is necessary because my network is hidden.
  • Click on Conections, then on next
  • Fill in “Home WWCF”, select WLAN, don't scan
  • Fill in name, select hidden checkbox, WPA pre-shared key
  • Close, choose select connections and connect

• Follow these instructions to become root and install an xterm.

• Set user password, lock the root account, install ssh

    $ sudo gainroot
    $ passwd user
    $ passwd root
    $ passwd -l root
    $ apt-get install ssh
    

• Formatted my MMC with two partitions, a 500 MB vfat (mmc1) and a 1.5GB ext2 (mmc2). Instructions here .