Hi Andrey,

You can use the Split Segment and Convert commands from the context menu shown when you right click a segment. I could not find a way to add an arc through the designer though... We will fix this in a couple of days and upload the updated designer source here.

Until then, you can insert an arc only by manually adding an entry in the shape library xml file. It should like

    <outline>
     <arc x="40" y="0" arc-width="20" arc-height="20" start="0" sweep="45" dash-style="Custom" width="-1" />
    ...

Stoyan

I guess because the shape outline must be a single closed path, and the end points of each outline segment must coincide with the end points of its adjacent segments. The designer enforces this condition by only letting you split existing segments.