For more information about the modpack and Infinity One (a dedicated server running the pack), please visit http://mc.siradio.fm
Brought to you by the folks at Split Infinity Radio (www.siradio.fm)
Type in the modpack name (Infinity Engine X) or paste the following url into the search box.
Finally, click Install at the bottom right of the launcher after you select Infinity Engine X from the list on the left. The launcher will handle everything else!