What happens when you hit Apply? And why have you made the second one, "MACINTOSH H," MS-DOS-FAT (FAT32)? You reaize that file sizes will be limited to 4GB with FAT32 and there are other restrictions. Is this a deliberate choice?
How much data do you already have on the original volume "Macintosh HD?"
Partitions must occupy contiguous physical space on a disk, so you may be able to add a partition to a disk, if there’s enough space left on it.
http://pondini.org/OSX/DU3.html
Read the rest of that page.
Are you aware that the first screenshot states "You may only split this partition into two"?
Message was edited by: WZZZ