What file system for sdcard for KitKat
This limitation is not due to the FAT filesystem : Since 4.4, Android only lets a special user group write on the card.

Your card could be in NTFS, or EXT or whatever more, you'll have the same problem.

The only way to bypass this limitation is to root your device, and install some 3rd party apps/patchs, or manuallay edit some files.