I know this doesn't immediately respond to the original poster's need for adding user access and modification of site pages/content, but I have not found ANY open source CMS to be of my liking. I am not a developer or designer. I just wanted a clean, intuitive way to separate content from layout. Even if it meant I had to buy both pieces, I was NOT going to go through the pain of managing a website again coding raw HTML, CSS, and VBScript.

I've looked at Joomla, Drupal, TYPO3, TYPOlite, MODx, SilverStripe, Dreamscape, Concrete, CMS Made Simple, and Website Baker (and others in less detail). I've found them to be noble in concept, but far too proprietary and disconcerting in terminology, usability, and application. Cryptic menus, confusing interfaces, disjointed administration. Each one I tried required numerous visits to the Help pages, user forums, tutorials, etc. Just to get a simple brochure site up.

My ultimate conclusion was that open source systems are conceived and written from the perspective of a developer or designer, someone who needs a framework to work upon. I needed (wanted) a complete infrastructure that provided everything, without my having to learn and install plug ins, educate myself on some other language, to eventually only end up with something that still required much fine tuning when I finally got the basics put together.

I'm hoping someone has a recommendation for you from which to start implementing some kind of user access without undue work. If you do end up deciding to transfer all of the site infrastructure to a CMS, I strongly recommend Expression Engine, even though it does cost. If not EE, I'd probably place MODx as my number one open source choice, although you will probably have to modify it before being able to roll your entire site into it.

I finally decided that I'd pay the $250 for EE instead of burning hours of my own time and potentially (probably) paying as much or more for a developer to get things the way I wanted them with an open source option. There is a no-cost version of EE, but it is throttled.

This comes from someone who really wants to support the open source community, but who found open-source CMS solutions as though they were created by techno-geeks who design software for their needs, who are already prepared to put the other layers in on top that ultimately create a complete solution. That's fine, but wasn't what I was looking for.

Good luck,

Chris