Migration Utility - OutOfBoundsException exporting

Error:

 I was trying to use the Migration Utility 6.1 Wizard to export a few process flow objects. It failed. Below is the log.

Storing table AU_PROJECT
Export failed.Reason: Index: 0, Size: 0
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Error Stack Trace
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java.lang.IndexOutOfBoundsException: Index: 0, Size: 0
at java.util.ArrayList.RangeCheck(Unknown Source)
at java.util.ArrayList.get(Unknown Source)
at com.adeptia.migration.ExportImportUtil.fetchProcessFlows(Unknown Source)
at com.adeptia.migration.ExportImportUtil.exportSubProcessFlow(Unknown Source)
at com.adeptia.migration.ExportImportUtil.exportProcessFlowForGroup(Unknown Source)
at com.adeptia.migration.ExportImportUtil.doExport(Unknown Source)
at com.adeptia.migration.RunMigration.invokeExport(Unknown Source)
at com.adeptia.ui.LogPanelDescriptor$1.run(Unknown Source)
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Cause:

Clients have encountered this issue when activities within that process flow have invalid XML or IDs

Solution:

Review any newly created or recently modified activities that are being exported to ensure they can be saved (valid XML/XSDs)