Can't create nested stimulus groups with range replicators

The attached experiment attempts to create a single, outer stimulus group that contains 10 inner stimulus groups, each of which contains 10 stimuli. It does so using the following nesting scheme:

Outer group
    Outer range replicator
        Inner group
            Inner range replicator
                Stimulus

The experiment fails to load, producing the following error message:

ERROR: An ambiguously named object was detected during parsing (connection phase).
Please ensure that all object names are unique.
Details: tag_name = <bg_${outer}_1>, reference_id = <id55510191>, instance_id = <0>

You can see why this is happening by running the experiment through MWParserTransformation.xsl and looking at the resulting connection XML:

<mw_connect parent="Outer group" parent_scope="" reference_id="id35803884">
  <mw_range_replicator reference_id="id35803888" variable="outer" from="1" to="10" step="1">
    <child tag="Inner group ${outer}" reference_id="id35803899"/>
  </mw_range_replicator>
</mw_connect>
<mw_connect parent="Inner group ${outer}" parent_scope="" reference_id="id35803899">
  <mw_range_replicator reference_id="id35803903" variable="inner" from="1" to="10" step="1">
    <child tag="bg_${outer}_${inner}" reference_id="id35803915"/>
  </mw_range_replicator>
</mw_connect>

Note that the XML connecting each stimulus to its stimulus group contains references to the outer range rep's loop variable ("outer"), but it isn't wrapped in the outer replicator.

It looks like MWParserTransformation.xsl handles nested replicators correctly only when the inner replicator is a direct child of the outer one.