Perhaps
this will help in finding the .htaccess file? Many hosts tend to hide this files for some strange reason.
If it's not there, download Mysidia again and grab a copy from the zip file and plop it in? This really does sound like a problem with the .htaccess file.
As for the class_path tweak, it would look like this, and you will need it on x10 hosting, but I am at least sure it's got nothing to do with the current problem:
PHP Code:
$this->root = "/home/caterpillarcave/public_html/";