Changes
/* Evaluation without parameters */
Expression="Context.Values["LK_OFFLINE"]!=null || Context.Values["GUIDREF"]!=null" />
<Label TextColor="#FFFFFF" IsVisible="{Binding ElementName=ExpressionEvaluator, Path=Result, Converter={StaticResource BoolToVisConverter}}" />
</StackLayout >
</source>
The Label should be visible as long as at least one of the context object's two named properties has a value.</tab>
