1) You will need to run a local version of Sakai. First configure it to store the files in the filesystem instead of the database.
2) Upload a file with a question.
The nighties are all configured like this so you should be able to test there.
A patch contributed by us (SAM-2859) that improved performance in Samigo when uploading html5 recorded audio can be applied for any kind of uploads in DeliveryBean.