Subdomain issue and a question

Hi.

As a joomla nerd for years I'm finally starting to branch out and explore some of the other exciting CMS systems out there. Contao looks very interesting and promising, and I can definitely see using it for many types of site projects.

I did have one issue and one question so far though:

[1] I created a subdomain on my primary domain as a place to install and test contao, contao.mydomain.com. First attempt I installed via contao.mydomain.com/contao/install.php and installation completed fine. Second attempt I installed via http://www.mydomain/contao/contao/install.php (subdomain folder happens to be of the same name), also a successful completion.

However, not really sure if/why that would make a difference, but it does seem to matter how the site is addressed to run it.

If I address the site via the folder path, http://www.mydomain.com/contao[/contao], the front- and back-end of the site work fine. If I address it via subdomain, contao.mydomain.com[/contao], neither front- nor back-end work correctly.

Via subdomain, I get the front- and back-end site to come up, but the text is raw, unstyled. Also, I cannot use the front- and back-end sample music accademy user accounts to log in - it is as if they are not recognized, and I get pushed to a secondary login page (also raw, unstyled).

In my mind, maybe I'm being naive, the system/site should look and behave identically in both cases. Anybody have insights/fixes?

[2] Unrelated to this, I was wondering if the admin folder (default "contao") can be safely renamed as an added bit of security. On my second installation attempt I did try renaming the folder prior to hitting install.php, but I got an error that seemed to indicate that pieces of the app/installation are looking for a specific folder name.

Thanks!