Activate the Invert Color in Windows 7 from C#

AS we know if you star the magnifier tool it has an option "Turn on the Color Inversion"... I want to have access to this feature from my C# .net 4.0 winforms application.  I tried with out success autohotkey and modifying the registry of windows and broadcast the new configuration. I know there is an app called NegativeScreen that work perfect, but I can't use it because this is for a Gov application.

Any help would be much appreciated

Thanks