Okay, I have something going that is working nicely. Here is the gist of it.
Schema looks like this:
my:Fields
my:Group
my:field
my:row
my:Group is a repeating group. my:field is a picture file. my:row has a default value of count(../preceding-sibling::my:Group)+1. This means that for a given InfoPath form, each row element is a different number.
In my WordML XSL file, I have a template that looks like this:
<xsl:template match="/ns0:myFields/ns0:Group1">
<ns0:Group1>
<xsl:for-each select="@ns0:*|@*[namespace-uri()='']">
<xsl:attribute name="{name()}" namespace="{namespace-uri()}">
<xsl:value-of select="." />
</xsl:attribute>
</xsl:for-each>
<w:tbl>
<w:tblPr>
<w:tblStyle w:val="TableGrid" />
<w:tblW w:w="0" w:type="auto" />
<w:tblLook w:val="01E0" />
</w:tblPr>
<w:tblGrid>
<w:gridCol w:w="4428" />
<w:gridCol w:w="4428" />
</w:tblGrid>
<w:tr>
<w:tc>
<w:tcPr>
<w:tcW w:w="4428" w:type="dxa" />
</w:tcPr>
<w:p>
<w:r>
<w:pict>
<w:binData>
<xsl:attribute name="w:name">wordml://<xsl:value-of select="./ns0:row"/></xsl:attribute>
<xsl:value-of select="./ns0:field2" />
</w:binData>
<v:shape id="_x0000_i1025" type="#_x0000_t75" style="width:100pt;height:50.25pt">
<v:imagedata>
<xsl:attribute name="src">wordml://<xsl:value-of select="./ns0:row"/></xsl:attribute>
</v:imagedata>
</v:shape>
</w:pict>
</w:r>
</w:p>
</w:tc>
</w:tr>
</w:tbl>
</ns0:Group1>
</xsl:template>
Since I generated the XSL using the WML2XSLT.exe by Microsoft, the XSL is a bit busier than it needs to be, but I only modified the center bits, where I need the picture element to repeat. What happens is exactly like what is demo'd in the blog I have linked to in my first post--the row element acts as part of the name attribute for the binData and again as part of the name attribute for the imagedata. Since the row element is always incremented by 1, the name stays unique. All I had to do was <xsl:apply-templates select="/ns0:myFields/ns0:Group1"/> at the point in my WordML XSL that I wanted my table with my pics.
Hope this saves anyone else struggling with this some time, and kudos and thanks to David Gerhardt for his blog entry, samples and suggestions.