Thanks Shade1974, I was able to load the GeoTiff file of around 10MB but I can't load file of around 1.72GB. I was able to load the same file in MapWindow Desktop application. I wonder if you could give me some clue about it.
I followed the steps as described above but with some minor changes. I would list down the steps, which may help other developers.
1. Open the MainForm in design mode from the demo project (DemoMap / Testviewer), check if the AppManager1 instance exist on the form otherwise drag AppManager from DotSpatial.Controls.Components to the Form.
2. Create a folder "Data Extensions" under the DemoMap project.
3. Copy folder "DotSpatial.Data.Rasters.GdalExtension" from DotSpatial.Data.Raster.GdalExtension project to Data Extension DemoMap project.
4. Build project DotSpatial.Data.Rasters.GdalExtension.
4. In DemoMap add reference to DotSpatial.Data.Rasters.GdalExtension and DotSpatial.Projections project.
5. In DemoMap add referenec to gdal_csharp.dll from /Data Extensions/DotSpatial.Data.Rasters.GdalExtension folder in the demo project.
Build and run the application. It will be able to load GeoTiff files and display accordingly.