Sadly it's not possible. Your host only run ruby on rails, a framework to create web applications, ruby in that case is a bit like php... so it only works if you call a page.
RoR use a routing system, from the url, to display and execute the page you want:
something like "http://myapp.com/admin_panel/create_user"
would go to the controller "admin_panel" and load the action "create_user" and display the html code for that page stored in a rhtml file.
furthermore, there is actually no folder "admin_panel" nor html file called "create_user" in that folder.
ANyway RoR is a very powerful system, that allow rapid web app creation... though it's a bit tricky at first to understand the way it works as it's really different from how you'd build an app with php.
