I just want to validate after reading through the books it appears that every
user (contributors) must have a full version of Contribute installed on their
machine, is that correct? I was orignally told when I called for more
information, that only the admin needed Contribute.

That is still the main set back when using Contribute. When you have multiple
users editing the website the choice to use this CMS can become very expensive.
Contribute, in my point of view, is only a good opsion when you do not have to
many users updating a website.