Yep Warbie's suggestion works for 12.0 too. Changed the setup.ini CmdLine:
CmdLine=/Liwmoe+ %TEMP%\dgnsetup.log SERIALNUMBER=XXXXX-XXX-XXXX-XXXX-XX PROD_ACT=0 PROD_REG=0 EREG_RUN=0 PRODUCTUPDATEFLAG=0 WEBREGISTRATION=0 DWUSMANAGER=0 /qn
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