Actually i`v created my own class for control named radPhotoViewer drived from class radcontrol. So, this isn`t allowing me to add add that control to page using Page.Controls.Add(radPhotoViewer). Not even in the radcontrols like radtoobar.Items.Add(radPhotoViewer).
Every method requires System.Web.UI.Control to pass as a parameter although i know all radcontrols are inherited from System.Web.UI.Control.