🚀 go-pugleaf

I don't know how actively FLAC converters are being developed for Audition, but there is active development of FLAC converters for other applications. For example, Winamp has a FLAC plugin and Winamp itself can do batch converting. You select one or more files in the Winamp playlist (say in WAV format, created in Audition and added to the Winamp playlist), then choose Send To -> Format Converter, then choose your FLAC settings. This approach has the disadvantage of needing more steps than just saving as FLAC directly from Audition, with the advantage of letting you to use more recent versions of FLAC converters.