Hi,
Texturepacker is an external program that will create assets for you for 2d sprites and animations. For this, several framework are available right within unity that will actually pack textures already, so I am not sure you need this at all in unity actually, but I might be wrong...
As for the uiToolkit, you should also find a more "non coder" friendly ui system in the asset store, or get one that has playmaker actions. nGui is very popular it seems.
Bye,
Jean