The data panel is tab separated, one row per point: the name first, then the value. You can paste straight from a spreadsheet. In the design panel, pick a part to change the two colors of the gradient, the line on top, the points, the interval of the axis, and the font.
The fill always reaches down to zero, the bottom edge of the plot area. The first and last points sit exactly on the sides, so the area spans the whole width. Drag the chart to move it and use the wheel to zoom. The zoom level sits at the bottom right.