You can use your SD card with KitKat, you just can't have one app write to another app's folder any more. If an app won't write to its own folder, copy the files in the folder, delete the folder and let the app recreate it. Then copy all the files back. (If you put the SD card into a computer to copy the files back, the permissions "problem" (it's more changing things so that the SD card now works the same as internal storage) doesn't exist, because Windows can't see the Android protection. But the app has to create the folder in order to write files to it.
If you're running 4.4.1, you can probably use Towel Root to root. If you're running 4.4.4, check on XDA to see if someone has come up with a way to root the 900V on 4.4.4 yet. (Probably not - it took months for geohot to come up with the exploit that Towel Root uses. Someone is just going to have to find one in 4.4.4 - the one TR uses was patched.)