Visit the offical Mozilla Firefox Add-Ons directory and install the DownloadTheAll! add-on.
Once the extension is installed in Firefox sign into your DMS account and visit My Downloads.
Click one of your available download links and choose 'DownloadTheAll!' when prompted to save your download file.
Sit back and watch your downloads complete happily! Problems downloading? Click here to open a support ticket and a member of the DMS Support team will get back to you ASAP.