I was able to successfully run the test sample. I'm using CLR4.0 controls in my project so I updated the sample accordingly.
After comparing my test with the given sample, I found that I was binding the grid in an "if (!Postback) {}" statement which was causing the paging to not work. This implies that the entire data must be retrieved upon every call to the page; wouldn't this cause performance issues for large amounts of data (which is why we'd be using paging in the first place)?
Thanks