Was this a good idea? 5TB Backup drive

Despair! I can't partition the new drive. I was guided through a download and installation of a program to allow the drive to work with both Mac and Windows files. Having installed the download, Disk Utility in El Capitan shows it formatted as being Mac OSX Journaled. However a message then appears to say that it isn't and has to be journaled from the Disk Utility File menu - an option that is greyed out. I have also noted that the new format is shown as "Apple UDIF read-only compressed (zlib) Media" and any attempt to change this fails.
The Seagate help site isn't helpful. Has anyone relevant experience that will lead me to Nirvana? (well, partitioning the new hard drive)?