I would start with iClone 6 and any Bonus Packs that are listed with it (click Bonus/Serial#), then Character Creator, and then 3DXchange with its bonus content. This will give you the main software.
From then on you can install pretty much from the top down. Some items are direct downloads, others, with an Install.RLD link, use a download manager. The ones under iClone 7 constitute content for Character Creator, so you should install those.