1. Installation:
Copy CS_DXF.DLL, CS_DWG.DLL, CS_HPGL.DLL to IrfanView\PlugIns\ directory.
For example  C:\Program Files\IrfanView\PlugIns\CS_DXF.DLL

2. Managing:
Setup CS_Manager.exe for changing image size of drawings.

3. Registration
3.1. Get license from http://www.cadsofttools.com/?PageName=order
page
3.2. Load CADSoftTools plugin Manager
3.3. Press CS_DXF button to show registration dialog fo CS_DXF.DLL Plugin. Use the same way to register CS_DWG.DLL Plugin and CS_HPGL.DLL Plugin.

Thank you for using CADSoftTools plugins.