I have Nero burning rom 6.6.1.4 and neither the burning ROM or Nero express (which I tend to use more often) recongise music files encoded in AAC or apple lossless EVEN though I have installed the relevant codecs in the right place (programs/common files/ahead/audioplugins). (Nero does fine with mp3, flac, ape etc)

OK I can burn these files using Foobar and the burning plugin that goes with it (that incidently relies on Nero burning ROM). But why can't I burn them with Nero? Why doesn't Nero recognise them. Clearly I have made some minor elementary error? Could someone please tell me where that error is?

any advice appreciated.

AAC should work. (Is it in the mp4 container?)

ALAC probably won't work. It's a proprietary Apple-only format, and not particularly well-supported anywhere. Avoid it when you can.