As Daniel mentioned this is a known issue.
The positioning command do not work using the GUI but they do work using MIDI mapping.
My workaround was to map the positioning command to buttons/knob on the controller.
In the following examples I mapped the position index for image and text to 2 knobs in the FX section of my DDJ-SZ2 controller.
Command channels and parameter will vary from controller to controller.
- Code: Select all
         <mapping name="FX1 KNOB(3) (E3-L)">
          <events>
            <MIDI type="CC" parameter="0x6" channel="0x5"/>
          </events>
          <controls>
            <control alias="fam(Video)[0x1].TitlerImagePlacementIndex"/>
          </controls>
          <preset name="Integer Map Fader/Knob">
            <parameters>
              <parameter object="map" key="backwardIntegerRange" value="0 0"/>
              <parameter object="map" key="backwardNormalRange" value="0 0"/>
              <parameter object="map" key="forwardIntegerRange" value="1 14"/>
              <parameter object="map" key="forwardNormalRange" value="0 1"/>
            </parameters>
          </preset>
        </mapping>
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         <mapping name="FX2 KNOB(3) (E3-R)">
          <events>
            <MIDI type="CC" parameter="0x6" channel="0x6"/>
          </events>
          <controls>
            <control alias="fam(Video)[0x1].TitlerTextPlacementIndex"/>
          </controls>
          <preset name="Integer Map Fader/Knob">
            <parameters>
              <parameter object="map" key="backwardIntegerRange" value="0 0"/>
              <parameter object="map" key="backwardNormalRange" value="0 0"/>
              <parameter object="map" key="forwardIntegerRange" value="1 14"/>
              <parameter object="map" key="forwardNormalRange" value="0 1"/>
            </parameters>
          </preset>
        </mapping>