- Allow WM_WINDOWPOSCHANGING when the control is size 0 to set initial size. - Combine multiple SetWindowPos calls in same processing line and make the flags like native. - Redo WM_NCCALCSIZE to match native. - Since Pager is a "transparent" control (except for its own buttons), the WM_ERASEBKGND needs to be passed to the parent. Also do the window offset like the native control does.