Migrating an addon from Kodi 16 – 17 (Confluence -> Estuary)

I originally posted in addon development but it was suggested that it may be more relevant here.

I have a script addon that functions perfectly under Kodi 15 and 16. It uses WindowXMLDialog to create and populate a dialog. However on Kodi 17 I see this

https://www.dropbox.com/s/yyqsmz0koytyhc….23.05.png

What you see there, is basically the content of my dialog, not displayed in a dialog.

Now, I’m not a great expert in Kodi programming (and I have to say I’ve found much of the doc. confusing, contradictory and outdated). But I have been using the following fragment at the top of my XML ( in resources/Default/720p/dialog.xml ) as follows

PHP Code:
<window id="1100" type="dialog">
    <
zorder>0</zorder>
    <
coordinates>
        <
system>1</system>
        <
posx>120</posx>
        <
posy>100</posy>
    </
coordinates>
    <include>
dialogeffect</include>
    <
depth>DepthDialog+</depth>
    <
defaultcontrol always="true">300</defaultcontrol>
    <
controls>
        <include 
name="DialogBackgroundCommons">
            <
param name="DialogBackgroundWidth" value="650"/>
            <
param name="DialogBackgroundHeight" value="600"/>
            <
param name="DialogHeaderWidth" value="570"/>
            <
param name="DialogHeaderLabel" value="$ADDON[script.service.unblockr 32020]"/>
            <!--<
param name="DialogHeaderId" value="1" />-->
            <
param name="CloseButtonLeft" value="560"/>
            <
param name="CloseButtonNav" value="9000"/>
        </include>
        <!--
Title-->
        <
control type="textbox" id="200">
            <
posx>20</posx>
            <
posy>70</posy>
            <
width>610</width>
            <
height>150</height>
            <
font>font13</font>
            <
textcolor>FFFFFFFF</textcolor>
            <
label>$ADDON[script.service.unblockr 32013]</label>
        </
control

etc.

I suspect (but havent proven) that the includes are failing on Estuary. I confess the include set was cribbed without genuinely understanding why – although I subsequently understand that they’re defined in Confluence’s ‘includes.xml’. As a non-skinner and artistic muppet, is there any way I can leverage the ‘current’ skin styling so as to

  1. Work with multiple skins and fit in with the skin style/settings
  2. Avoid having to carry / implement all the visual attributes and deal with skin changes smoothly.