I found that this is working if we are extending the SelectRenderingForm class. The problem that I am facing now is, SelectRenderingOptions model is not returning the list of rendering items to be appeared in the "Select a Rendering" dialog when we override the OnLoad method on the extension/derived class.
But, If we put below line in the very beginning of the OnLoad method then it is working as expected.
SelectRenderingOptions selectRenderingOptions = SelectItemOptions.Parse<SelectRenderingOptions>();
Instead of keeping next to the following line:
IsOpenPropertiesChecked = Registry.GetBool("/Current_User/SelectRendering/IsOpenPropertiesChecked");
If anyone hasknow other solutionssolution, please let me know!