There is a common problem on some devices that prevents recording on rooted Android 4.4. The problem comes from the device not being able to write files due to your root settings. Here is how to fix:

1. Install SuperSU app from Google Play

2. Open SuperSU and allow it to delete your other Super User apps.

3. Go to SuperSU's settings, and install SuperSU as a system app.

4. Reboot the phone and try recording the screen again.