Software sources will not run Ubuntu

non standard PPA caused a problem with software installation tools i.e. they would not run to allow edit removing required this method:
'
Go to repogen.simplylinux.ch.
Select your Country and Ubuntu Release.
For the default set of repositories, you need to enable these repositories.

• All of the Ubuntu Branches repositories.
• Security - Important Security Updates.
• Security Sources Repository
• Updates - Recommended Updates
• Updates Sources Repository

If you want to install software from Canonical Partner Repositories (closed source software), enable the Ubuntu Partner Repositories (both of them).
Enable any 3rd party repository you wish to enable.
Now, click the Generate List button at the bottom of that page and you'll see your generated sources.list.

Replace the old sources.list with the new one

Run the following commands in a Terminal.

sudo mv /etc/apt/sources.list /etc/apt/sources.list.old
gksudo gedit /etc/apt/sources.list

Copy/paste all the text from the newly generated sources.list to this file. Save it and close Gedit.
Now, update apt.

sudo apt-get update

This will update your repository index with the current sources.list and then you can install any software using Software Center, Synaptic or apt-get.'
http://askubuntu.com/questions/124017/how-do-i-restore-the-default-repositories

Installing Ruby on Rails used the manual method rather than the scripts on offer as the scripts point to unsupported versions of Ruby:
http://blog.sudobits.com/2012/05/02/how-to-install-ruby-on-rails-in-ubuntu-12-04-lts/

This has a useful command list & runtime instructions also:
http://tutorialsave.com/how-to-run-ruby-on-rails-on-a-mac/

Creating desktop shortcuts in 12.04 Ubuntu with Gnome

Creating desktop shortcuts in 12.04 Ubuntu with Gnome:

sudo apt-get install --no-install-recommends gnome-panel

#then

$ gnome-desktop-item-edit ~/Desktop/ --create-new