Hi Paul,
That did it! Sort of, so the issue was that I was exactly following the instructions from the ADI GNURadio wiki page, and there's a slight issue there. When you first install GNURadio on the ARM, you run:
cmake -DCMAKE_BUILD_TYPE:string=Release -DENABLE_DOXYGEN:bool=false ..
to setup the configuration, this sets the default build directory to /usr/local, but when I was following the instructions for compile IIO only, it instructs you to run:
cmake -DCMAKE_BUILD_TYPE:string=Release -DENABLE_DOXYGEN:bool=false -DCMAKE_INSTALL_PREFIX=/usr ..
which sets the iio build directory to /usr instead of /usr/local. I rebuilt my IIO blocks changing the install prefix to /usr/local and I can configure parameters at runtime as advertised. I'm not sure if that was a minor mistake in the directions or if that was intentional.
Thanks for sticking with me through this!
-Austin