Hello Mark,
The evaluation is fully-functional and you don’t require a retail license to preview the report with Nevron Gauge.

If you can see the gauge and it is not displaying your data in Preview, this means that probably you haven’t configured the Value expression.

I have followed the instruction to create my first guage.  I attempt to preview the guage in Microsoft Visual Studio for SQL 2008 R2 the guage appears but does not show my data.  Do we need the real license to preview?

Thanks,

Mark