There isn't a previous version of RadGauge for ASP.NET AJAX. The control was introduced in the Q3 2012 release for the first time.
The scales of the three gauges are created by the gauges themselves - including the major ticks, the minor ticks and the labels. The image background only servers to add the dial-like display and the unit of measurement. You can see if for yourself by examining the demo from your local installation and removing the background images. What will be left is the gauges themselves.
the Telerik team
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