Trying to get started with CGI

[#1]

I have activated CGI on my site a few weeks ago. It shows as activated in member centre.
From what I've read, I should now get new web space at the address http://ccgi.username.plus.com/
(I'm assuming that I replace username with my user name).
When I access this address in a web browser I get 403 Forbidden.
In fact I still can access the original space via FTP and browser and it works (except for .php and .html that calls .php, these files get set to 0 bytes when uploaded).
Confused...

[#2]

Yes, username in the domain name
You could get a 403 error if you have no default file in the URL, as that is like asking for a directory listing (I don't think we can set permission to list the root directory using http). If you are using the URL http://ccgi.username.plus.com/ (ie without a filename) in your browser, then you should have a default file, eg index.htm, default.htm, index.html, etc. and it should have execute permission applied.
The 0 byte file issue seems odd. Are all uploaded files showing as 0 bytes?

[#3]

Checking your CGI space, I can see that you've uploaded some files, including an index.html one. Browsing to ccgi.username.plus.com (replacing username with your username) is now showing the index file you've uploaded.