Ant,
Welcome to the forum. I've moved your post from Release Announcements to the Installing Software section.
To get a bit more information about what may be happening, please try running the application from a terminal window.
Open a terminal window by pressing the Ctrl Alt and T keys together.
In the window that opens enter the following command followed by enter
Please report back what happens, include any/all system messages which appear in the terminal window.
lite-software: 1. asks for authentication 2. suggests to update software sources 3. lite software prompt to install/remove appear 4. list of available software appears for a second or two 5. !!! AND AFTER THAT IT DISSAPEARS and again appears prompt to install/remove lite software ....
Thank you, seems like it might be skipping an important stage.
Can you open a terminal again and provide the result of this command.
Post the results back to show us information about your set up so we can try to reproduce the problem.
When it asks you to update sources are you selecting YES? If you intend to install something you should select YES to update sources. You don't need to if you only intend to remove something. (I find that dialogue is a little wonky about that specific case and should probably be eliminated and just automatically update sources every time.) Also you need an internet connection to update the sources.
TC