Try this in playground

var x = 100;
var y = 100;
ctx.beginPath();
ctx.moveTo(x, y+200);
ctx.arcTo(x+200, y+200, x+200, y, 200);
ctx.stroke();

The fix is relatively straightforward, but I'm not going to prepare it for a defunct project. If you are still supporting canvas2svg, write back and I'll consider it.