Hi TCaldwell!
I am not very familiar with that website. However, taking a look at it, the rules are much the same as they are for traffic exchanges.
It would be safe to add any of the affiliate pages from GDI, except for the sign up page itself as it does have an exit "pop-up", in that you have to click "OK" to exit the page. But, all of the other pages are safe. They contain no pop-ups, and they do not break frames.
I hope this helps. If you have more questions please ask away because, really, the only stupid question is one that is not asked. We all have to start somewhere, and it would be a crime not to use everyone's knowledge to your advantage.
Have a good day and good luck! I hope it works great for you!
Vincent Parker