Smartware Pro Dropbox backup

I am trying to backup the whole of my dropbox onto a WD Mycloud device. I have managed to backup up some of my folders and files but for some reason it is not backup up the whole of my account. There is plenty of room on MyCloud.
Is there a limit to the number of subdirectories it will backup? or number of files ? which is preventing a full backup

Many thanks

Have you read all of the Help information to Retrieve that is provided in SmartWare Pro, Help tab?

What type of files are you having problems with?

I am not trying to retrieve, I am trying to backup the documents from my dropbox account to the Mycloud. The files are normal documents, spreadsheets and pdf files in directories and subdirectories. The backup has copied some to the area but not all. The files that it has not backed up are not one type or even belonging to one subdirectory