This article explains what the difference is between the two types of "storage" on Limecraft, Cloud Storage and Managed Media.
When uploading media to the Limecraft Workspace, there is automatically a proxy version of the media created and stored as Managed Media. The original media, or the high resolution version of the media, is stored in the Cloud Storage. 
In fact, Managed Media represents the hours of media currently managed in your Limecraft Workspace(s). Cloud Storage represents an actual storage, managed by Limecraft. It makes your original media available for you for download from any location as it is stored in the Cloud.