OxyPlot.Metro from NuGet: chart completely empty!

I have been using OxyPlot.Metro in a Caliburn.Micro based Windows 8 application.

I have my View.xaml something like this:

// xmlns:oxy="using:OxyPlot.Metro"  
<oxy:Plot x:Name="Chart" Model="{Binding PlotModel}"/>

The PlotModel is a notifiable property in ViewModel.cs and it is initialized during view-model construction pretty much like this:

PlotModel = new PlotModel();
PlotModel.Axes.Add(new LinearAxis { Title = "X", Position = AxisPosition.Bottom });
PlotModel.Axes.Add(new LinearAxis { Title = "Y", Position = AxisPosition.Left });

The display of curves is updated based on user selection in an event handler in the View.xaml.cs file:

Chart.Model.Series.Clear();
var newSeries =new LineSeries { 
    ItemsSource = SomeListOfPointObjects, DataFieldX = "X", DataFieldY = "Y" };
Chart.Model.Series.Add(newSeries);
Chart.InvalidatePlot();

With the old NuGet version 2014.1.1.1 this is working well and the selected curves are properly displayed in the chart.

However. When I upgrade to the latest OxyPlot.Metro version from NuGet (as of this writing version 2014.1.319.1), or for that matter any version released after 2014.1.1.1, the above code produces a white, emtpy chart!

Has anyone else experienced this problem? In that case, did you find a workaround to the issue?