Hi Driss
Which version of Essential Studio are you using?
You should not have any problems dragging and dropping the GridGroupingControl if you are using the 2.0 version of the .NET Framework (VS 2005).
In case of the 1.x Framework (VS 2002/2003) the VS.NET Designer does not add
theselines for the other assemblies that are referenced. You can just copy and paste these lines from one of the samples that ship as a workaround.
The code expects the scripts and images to be under /Syncfusion/Resources/GroupingGridWeb where /Syncfusion is a virtual root directory under IIS as noted
here.
Regards
Arun