Joey,
That's going to be a question for the NI sales or support team.
Start by going to ni.com/ask. They may actually have something on the website. This is a very powerful site for getting support, finding software and drivers, as well as patches. If you start a support question, you will be given a bunch of links. Be sure to enter the model or name of the signal accessory as well as other pertinent information in the question, as this is the query to search all of NI's databases.
Unfortunately, I don't think you will get a schematic diagram for this. It is proprietary technology, and National Instruments is very protective of such information, as they should be.
If you have a specific question, perhaps someone here can help.