The last AVStoDVD version which supported CCE was version 1.1.3. Very old, not really recommended today...
Current versions only support HCenc and FFMpeg. By default FFMpeg can only be used for high bitrates in CBR mode, but you can get much higher quality from FFMpeg if you use my ffmpeg_VBR plugin:
http://forum.doom9.org/showthread.ph...23#post1745423
It is a small download, read the included PDF manual and decide if you want to check it out...
Cheers
manolito