How to plot multiple (x,y) series on the same axes with Chaco?

I have several sets of (x,y) data that I'd like to plot as line plots on the same figure. I have no trouble with matplotlib doing this, but I cannot get the same results with Chaco. Code and output are shown below.

My matplotlib-based code looks like this:

for track in tracks:
    xw = np.array(track['xw'])
    yw = np.array(track['yw'])
    plt.plot(xw, yw, 'b-')
    if not plt.gca().yaxis_inverted():
        plt.gca().invert_yaxis()

My Chaco-based code looks like this:

for track in tracks:
    x = np.array(track['xw'])
    y = np.array(track['yw'])
    plot = create_line_plot((x,y), color='blue', width=1.0)
    plot.origin = 'top left'
    container.add(plot)
    if track == tracks[0]:
        add_default_grids(plot)
        add_default_axes(plot)

My matplotlib-based output looks like this:

My chaco-based output looks like this:

The problem with my Chaco-based code above was that I was using an OverlayPlotContainer (container). Because of this, each plot (from create_line_plot) was being drawn with its own axes rather than each plot being drawn on the same set of axes. The following works:

    pd = ArrayPlotData()
    plot = Plot(pd)
    for ii, track in enumerate(tracks):
        x = np.array(track['xw'])
        y = np.array(track['yw'])
        x_key = 'x'+str(ii)
        y_key = 'y'+str(ii)
        pd.set_data(x_key, x)
        pd.set_data(y_key, y)
        plot.plot((x_key, y_key), color='blue', origin='top left')