Robert, I might have found a little bug.
After I've drawn a polyline and want to draw another polyline, I click the icon but now the drawtool isn't a polyline but just a line. But if I click antother icon and then click the polyline icon again then the drawtool will be a polyline again. This behavior is the same in your sample in the code gallery, maybe you want it that way, but to me it doesn't make sense, so I looked at the code and found out that:
when enterstate drawToolsLine DrawTool.POLYLINE is passed to the activateDrawTool function.
<s:State name="drawToolsLine" enterState="activateDrawTool(DrawTool.POLYLINE, null)"/>
but when the image is clicked DrawTool.LINE is passed to the activateDrawTool function.
<mx:Image click="{(currentState == 'drawToolsLine')?activateDrawTool(DrawTool.LINE, null):currentState = 'drawToolsLine'}" ......
I guess it's supposed to be the same in both these cases, DrawTool.POLYLINE if that is the expected tool. I changed the code to this and it works as I want it to.
Just wanted to report this because to me it looks like a typo or something like that...