The ArcReader control (AR.ocx) that is part of ArcReader 8.x is not supported for third party developers. This control is not intended for use and is not supported by Technical Support at ESRI.
The Publisher extension at ArcGIS 9 does provide the ability to use the ArcReader developer control (ArcReaderControl.ocx) to build custom ArcReader applications.
- ArcReader 9 x
- ArcReader 8 x