Re: I want flat dialogue levels, do I use Compressor, Limiter, Normalize, or what?

You could export your dialogue (w/o music/SFX) as AIFF or WAV files, run them through the Levelator and replace the dialogue with the resulting processed file.

If you've got noise floor issues, music or other dynamic issues it may cause more trouble than it's worth, but it can work wonders on the right source.