Thank you for reaching us out.
The reason why Rows is underlined is that the element is not correct identified - there is no such control Grid.
You probably need to use RadGridView or HtmlTable
controls' properties to access the grid's rows.
you could read further details how elements are identified in the Progress Testing Framework. Also I would like to provide a coded sample
that automates some actions against a html table which could be used for further reference.
I hope this information will be useful for you to proceed automating your application. In case of further queries do not hesitate to contact us again!