I'm running 4.3 rooted and I've used Galaxy Call Recorder for the last 6 months with no problems. The dev has put this on the Play Store:
"As this program is using Android Standard API the two-way recording will work only on some devices such as Samsung Note 3/2, Galaxy S4/3/2."
"WARNING: The app does not work on S4 and Note 3 with KitKat 4.4.2 if records are being stored on a SD card. It is highly recommended for Note 3 users not to update to KitKat 4.4.2".
So it appears they might be trying to restrict call recording in KitKat.