BuildReportTool error in batchmode

gistfile1.txt

ArgumentOutOfRangeException: StartIndex cannot be less than zero.
Parameter name: startIndex
  at System.String.Substring (System.Int32 startIndex, System.Int32 length) [0x00013] in <d7ac571ca2d04b2f981d0d886fa067cf>:0 
  at BuildReportTool.Util.GetApproxSizeFromString (System.String size) [0x00021] in /Users/stephan/code/stack4/client/unity/stack4next/Assets/BuildReport/Scripts/Editor/Utility/BRT_Util.cs:491 
  at BuildReportTool.ReportGenerator.ParseSizePartsFromString (System.String editorLogPath) [0x0019a] in /Users/stephan/code/stack4/client/unity/stack4next/Assets/BuildReport/Scripts/Editor/ReportGeneration/BRT_ReportGenerator.cs:559 
  at BuildReportTool.ReportGenerator.GetValues (BuildReportTool.BuildInfo buildInfo, System.String buildFilePath, System.String projectAssetsPath, System.String editorAppContentsPath, System.Boolean calculateBuildSize) [0x00106] in /Users/stephan/code/stack4/client/unity/stack4next/Assets/BuildReport/Scripts/Editor/ReportGeneration/BRT_ReportGenerator.cs:1882 
  at BuildReportTool.ReportGenerator._GetValuesBackground (BuildReportTool.BuildInfo buildInfo) [0x00001] in /Users/stephan/code/stack4/client/unity/stack4next/Assets/BuildReport/Scripts/Editor/ReportGeneration/BRT_ReportGenerator.cs:2404 
  at BuildReportTool.ReportGenerator.CreateReport () [0x000ba] in /Users/stephan/code/stack4/client/unity/stack4next/Assets/BuildReport/Scripts/Editor/ReportGeneration/BRT_ReportGenerator.cs:331 
  at BuildScript.BuildAndroid () [0x000cb] in [...]/Assets/Scripts/Editor/BuildScript.cs:44 
 
(Filename: <d7ac571ca2d04b2f981d0d886fa067cf> Line: 0)