I didn't use www.example.org, I used my own site address. When I put that line into the /mysite/_config.php file, every time I try to load the website, it tries to load up install.php. I've removed that line, and it still tries to load install.php, so now I can't access anything! I can't fix that, so I'm going to have to reinstall the whole thing. Let's see if the Page Type works this time...
That should not matter.
Does the site work as normal without the HomePage.
Do you get any errormessages?
Can you pastie.org your HomePage.php file?
Sorry for not replying for a while - I've been away.
I re-installed SilverStripe, and all works! I've got no idea why it didn't before, but thank you to everybody for your help! Now I'm off to work with this excellent CMS.