Perhaps I do not understand the issue very well.
1. I do not think that there is a bug in the sdk example. The sdk example does not include a pan zoom behavior. This is something that you need in your application and it is up to you to modify the code, or even create new code so that it fits your case. Perhaps in the future we may include a pan-zoom behavior and update the code accordingly, but currently the sample demonstrates synced track-ball-like annotations without zooming.
2. I tried calling this code chart.ConvertPointToData(position)
when the chart is empty (when there was a series with no data points and when there was no series at all). I did not get an exception. Plus I looked around in the sdk sample and I think that this code is never executed on an empty chart. So this is again custom logic in your application that you should build-up on your own. If you think that there is a bug you can open a new support ticket and mark it as a bug report (you can also include a project that demonstrates this).
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