LiquidThreads with the naive installer, it installs fine and it does not break MediaWiki. When you go to a talk page the system still breaks because the "thread" table is missing. When you read the documentation, it is quite obvious that LiquidThreads would fail in this way. There is a script that helps you to install the tables and as I expected that it would be relatvely easy to create a script for the complete install and uninstall of LiquidThreads I looked into this.
I asked MinuteElectron to help me out and provide me with an example, he added one line to the standard "download.sh". For the uninstall he added a few lines to the "uninstall.sh" and added a file with the names of the tables that were to be dropped.
I now have a template for creating install scripts for extensions. I will have to ask Kim or MinuteElectron to update SVN with my scripts because if I were Brion, I would not trust me with SVN either.