Figured it out:
Code:
alias comtest {
  .comopen a MSScriptControl.ScriptControl
  if (!$comerr) && ($com(a,Language,4,bstr,VBScript)) && (!$comerr) {
    noop $com(a,ExecuteStatement,1,bstr,MsgBox(Now))
    if ($com(a)) && (!$comerr)  .comclose a
  }
}
execute the alias and once the window is opened, go back to mirc and type /comclose a, close the window and repeat, mirc should crash.

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