Ah, the forums screwed it somehow... I wanted you to use this:
<base href="[[++site_url]]" />
Moreover, your $modx_base_url should be "/" or anything, which means a directory, not an URL.
I think you can set the site_url setting in your context settings. Click on "web" in the resource tree and go to "Context Settings". If there is no setting called site_url create it. You don't have to fill in all the fields. Just use site_url as key and
http://your-domain-name.tld as the value.
Clear cache, see what happens.
[ed. note: chrisissorry last edited this post 12 years, 4 months ago.]