FTP connections for Drupal is configured by default in cloud images so you can install modules from the Administration panel.
I have launched a fresh Bitnami Drupal AMI in Amazon Web Services and tried to install a new module from URL and it worked for me. It is true that appeared an intermediate step showing a page asking for FTP settings but the form was filled. Didn't it for you?
You can check your FTP settings at
/opt/bitnami/apps/drupal/htdocs/includes/filetransfer/filetransfer.inc config file.
Hope it helps,