"Error with ValueSubgroupIterator and nominal values"

I've run into a strange problem.  If I save the process at the end of this message to a file, restart RM and load it, when I try to run it I am getting the error message:

NumberFormatException caught:
For input string: "all"

However, if after loading it, I first select ValueSubgroupIterator, click Edit List for "attributes", and change the values from "all" to "above p" and then back to "all" (thus restoring the process to its initial form) before running the process, it runs successfully!

Seems like there is a parsing glitch in the code?  This is RM 4.3 Zaniah branch built yesterday.

<operator name="Root" class="Process" expanded="yes">
    <operator name="NominalExampleSetGenerator" class="NominalExampleSetGenerator">
    </operator>
    <operator name="ValueSubgroupIterator" class="ValueSubgroupIterator" expanded="yes">
        <list key="attributes">
          <parameter key="att1"	value="all"/>
        </list>
        <operator name="DecisionTree" class="DecisionTree">
        </operator>
    </operator>
</operator>