Changing preview duration is broken

[BigFlubba]

I've been trying to change the time for previews and it always defaults back to 800ms. In the settings file it stays, but the interface shows 800ms and the previews are only 800ms.

<?xml version="1.0"?>
<GeneratorSettings xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <Thumbnails>
    <Intervall>10</Intervall>
    <Width>1920</Width>
    <Height>360</Height>
    <AutoWidth>true</AutoWidth>
    <AutoHeight>false</AutoHeight>
    <AutoIntervall>true</AutoIntervall>
  </Thumbnails>
  <ThumbnailBanner>
    <Columns>4</Columns>
    <Rows>5</Rows>
    <TotalWidth>1024</TotalWidth>
  </ThumbnailBanner>
  <Preview>
    <AutoWidth>true</AutoWidth>
    <Width>1920</Width>
    <AutoHeight>false</AutoHeight>
    <Height>360</Height>
    <FrameRate>30</FrameRate>
    <Start>0</Start>
    <Duration>20000000</Duration>
    <SectionCount>10</SectionCount>
    <DurationEach>20000000</DurationEach>
    <MultipleSection>true</MultipleSection>
  </Preview>
  <Heatmap>
    <Width>800</Width>
    <Height>40</Height>
    <AddShadow>true</AddShadow>
    <ShowMovementRange>true</ShowMovementRange>
    <TransparentBackground>true</TransparentBackground>
  </Heatmap>
  <General>
    <GenerateThumbnails>true</GenerateThumbnails>
    <GenerateThumbnailBanner>true</GenerateThumbnailBanner>
    <GeneratePreview>true</GeneratePreview>
    <GenerateHeatmap>true</GenerateHeatmap>
    <SaveFilesToDifferentPath>false</SaveFilesToDifferentPath>
    <ExistingFileStrategy>Replace</ExistingFileStrategy>
  </General>
</GeneratorSettings>