Step 2 - Customize Toolbox
Right-click the toolbox and select Customize
Toolbox. Make sure the .NET Framework Components
tab is selected. Click the Browse button and select the
DLL from the folder you downloaded it to. Finally, click OK
and the SmartScroller appears in your toolbox.

Step 3 - Drag and Drop
All that's left is to drag the control from
the toolbox onto your ASPX page just like any other control.