This is a workflow to load zdab, convert to RAT::DS (root) and then in a separate script plot the results.

PlotCAEN.cc

// To run this open ROOT and do
//     .L PlotCAEN.cc+
//     PlotCAEN( "output_filename.root", 10 );
// where the number is the event id you'd like to view the waveforms of
#include <RAT/DU/DSReader.hh>
#include <RAT/DS/Entry.hh>
#include <RAT/DS/Digitiser.hh>

#include <TCanvas.h>
#include <TGraph.h>

void PlotCAEN( const char* fileName, size_t eventID )
{
  RAT::DU::DSReader dsReader( fileName );
  const RAT::DS::Entry& rDS = dsReader.GetEntry( eventID );
  if( rDS.GetEVCount() == 0 ) // No events to plot
    return;

  TCanvas* c1 = new TCanvas();
  c1->Divide(4, 4);
  const Digitiser& digitiser = rDS.GetEV( iEV ).GetDigitiser();
  for( size_t iWaveform = 0; iWaveform < 8; iWaveform++ ) // There are 8 possible CAEN channels
    {
      if( !digitiser.ExistsWaveform( iWaveform ) ) // Not all of which are used
        continue;
      c1->cd( iWaveform + 1 );
      TGraph* graph = new TGraph();
      std::vector<UShort_t> waveform = digitiser.GetWaveform( iWaveform );
      for( size_t iSample = 0; iSample < waveform.size(); iSample++ )
        graph->SetPoint( iSample, iSample, waveform.at( iSample ) ); 
      graph->Draw("AL*");
    }
  c1->cd();
}

zdab2root.mac

# To run this simply do 
#     rat zdab2root.mac -I input_filename.zdab -O output_filename.zdab

/PhysicsList/OmitAll true

/run/initialize
##########EVENT LOOP############
/rat/proclast outroot
##########EVENT LOOP############
/rat/inzdab/read_default
exit