Creating a custom parameter similiar to Galapagos's "Genome" param

I'm developing a custom component in C# in Visual Studio and I'd like the component to have a parameter with a similar functionality as Galapogos's "Genome" parameter.  Specifically, I'd like the user to be able to click on the parameter and drag a wire that can connect to a slider which it will then be able to output values to (see attached image of Galapagos's "Genome" param wires). 

I have the code working to control the slider from within my component, but I could use assistance on drawing this custom param to the screen.  Any pointers or advice would be much appreciated.