ModX Revolution is a pretty slick content management system for non-programmers. But, it has a few issues.
For one thing, you cannot take a website developed on one server and drop it into another server without re-installing the framework completely.
More importantly, it has seriously aggressive caching, that sometimes is counter-productive. My photography site is accessible from more than one domain name running on nginx. I found out the hard way that if someone accessed it by one domain name and then someone else by another, the first to the cache would generate links that had the full url to the first domain name in them. For most sites that's not a problem but when you're running JSON with a reactive website, the links that are crossing domain names will fail to work due to security settings in the server and browser.
I ended up doing what I probably should have done the first time which is redirect all requests for one domain name to the main one automatically with the web server.