Known bugs
When performing the same conversion twice, a second file is added to the list (but there's no second file on the server, the problem lies within the meta-data).
The upload procedure can't be performed twice at a time.
The meta-data access is faulty. The local data are not updated when another user changes something on server. So only the last update of the meta-data is saved.
When a file is added to a file bloc (for example when converting) the item is drawn out of the bloc (but is selectable anyway).