If you get a error screen "Mod Sorting Cycle", go to appdata/roaming/.technic/modpacks/the-kat-factory/ and delete "config" folder, and the problem is solved! (this "Bug" occur random)
Type in the modpack name (The Kat Factory) or paste the following url into the search box.
Finally, click Install at the bottom right of the launcher after you select The Kat Factory from the list on the left. The launcher will handle everything else!