Thanks so much for your help Ottogal and microcipcip.
I managed to get it working in 2 different ways.
Using the TV as per Ottogal’s suggestion:
Ditto Call:
[[Ditto? id=`ditto57` &parents=`10` &depth=`10` &seeThruUnpub=`1` &tpl=`downloadsRow` &filter=`tvadd-to-downloads,yes,7`]]
TV - I created a TV called "add to downloads" with:
input type as checkbox,
input option values as Yes==yes and
default value as no
Then click yes for each product that has a download (eg can be done at time of linking a pdf file).
&tpl=`downloadsRow`:
<tr>
<td class="col41">[+pagetitle+]</td>
<td class="col42">[+description+]</td>
<td class="col43"> <a href="[+product-image+]" rel="lightbox" title="[+pagetitle+] : [+description+]"><img src="[+product-image+]" id="[+id+]" /></a> </td>
<td class="col44"> [+phx:if=`[+product-download-catalogue+]`:isnot=``:then=`<a href="[+product-download-catalogue+]" title="Catalogue for [+pagetitle+]" target="blank"><img src="/equity/images/mix/pdf-icon.png" /></a>`+] [+phx:if=`[+product-download-install-manual+]`:isnot=``:then=`<a href="[+product-download-install-manual+]" title="Installation Manual for [+pagetitle+]" target="blank"><img src="/equity/images/mix/pdf-icon-Y.png" /></a>`+] [+phx:if=`[+product-download-technical+]`:isnot=``:then=`<a href="[+product-download-technical+]" title="Technical Data for [+pagetitle+]" target="blank"><img src="/equity/images/mix/pdf-icon-B.png" /></a>`+] </td>
</tr>
Using an outer PHx statement in the downloadsRow template:
Ditto Call:
[[Ditto? id=`ditto157` &parents=`10` &depth=`10` &seeThruUnpub=`1` &tpl=`downloadsRow4`]]
&tpl=`downloadsRow4`:
[+phx:if=`[+product-download-catalogue+]`:isnot=``:or:if=`[+product-download-install-manual+]`:isnot=``:or:if=`[+product-download-technical+]`:isnot=``:then=`
<tr>
<td class="col41">[+pagetitle+]</td>
<td class="col42">[+description+]</td>
<td class="col43"> <a href="[+product-image+]" rel="lightbox" title="[+pagetitle+] : [+description+]"><img src="[+product-image+]" id="[+id+]" /></a> </td>
<td class="col44">
[+phx:if=`[+product-download-catalogue+]`:isnot=``:then=`<a href="[+product-download-catalogue+]" title="Catalogue for [+pagetitle+]" target="blank"><img src="/equity/images/mix/pdf-icon.png" /></a>`+]
[+phx:if=`[+product-download-install-manual+]`:isnot=``:then=`<a href="[+product-download-install-manual+]" title="Installation Manual for [+pagetitle+]" target="blank"><img src="/equity/images/mix/pdf-icon-Y.png" /></a>`+]
[+phx:if=`[+product-download-technical+]`:isnot=``:then=`<a href="[+product-download-technical+]" title="Technical Data for [+pagetitle+]" target="blank"><img src="/equity/images/mix/pdf-icon-B.png" /></a>`+] </td>
</tr>
`+]
Both work fine - just have to work out how to get Ditto to order by column1 and then by column 2
Thanks again to everyone that helped on this.