Looks like a great plugin. Couple of quick pre-usage question.
1/ I need a way of viewing uploaded documents without downloanding them first (not to edit, just to view) for example using the Google Docs Embedder plugin. Does your plugin allow this or do you know a way that I can integrate your plugin with some other tool like the GDE?
2/ With your plug in, if documents are only available to logged in users, is their location masked or does the file remain secure so that the documents cannot be access by directly navigating to the files URL?