"Download/viewing monitoring and alarm"
I think bulk download option is not a desirable feature. I perceive OpenDocMan as a document sharing and access control solution. Personally I would not like someone be able to download 1GB of company info in a batch. To enhance a company protection against dishonest behaviour I would rather suggest an alarm setting if somene is viewing say 10 files in 10 minutes an alarm is sent to the admin and activity could be investigated.