Sorry, we are unable to understand your requirements properly. Can you please clarify what do you mean by a customized flag? Is it an image or you want to draw flags on the chart yourself? Also it would be helpful if you can provide us with some pictorial representation.
Let’s use your example:http://jsfiddle.net/canvasjs/u50cqf09/
My question is the following:
1. Is it possible to place the chrome icon in an arbitary position? for example, (35,20).
2. Instead of chrome icon, can we draw a square and place a number in it? Just like draw on a canvas?
Yes, you can place an image at any position you like. You just need to provide the pixel co-ordinates position to the top and left CSS properties of image. You can also make use of convertPixelToValue and convertValueToPixel methods provided in the library.
For your second query, You can draw anything you like on the canvas. Please take a look at this jsFiddle.