Centova Cast isn't involved at all in the actual processing of audio for your streams. It is a control panel for ShoutCast/IceCast and its associated source software products, which provide that functionality. So anything we implement as options in Centova Cast needs to be supported by the underlying software.
In brief, normalization isn't supported by any of the console-based source applications currently available. But if anyone adds it (perhaps sc_trans v2 does/will include it?) we'll be on top of it.