develop a componen

hi!,
i want to develop a own component but i don't know how i can start. i was read "BenSitler_Custom_Components_Manual.pdf" and copied the example, add all the references, but when i want to build it have errors like GH_Boolean it's not defined. i use vb 2010 framework 3.5 and grasshopper 0.9.0076. Best