Hi Jordan,
Nice to hear that you can use my code! I just tried to reproduce your problem on my machine (Ubuntu 12.10, GNU Radio v3.7.2.1-263-g78551a56) but all seemed to be fine.
So here are some guesses that come to my mind:
Did you make sure to reload the block list if GRC was already open by using the respective button on the top or did you restart GRC inbetween? You could also check (assuming you are on linux) if the blocks' XML files are placed in '/usr/local/share/gnuradio/grc/blocks' ? The 'install' output also shows where it copies stuff. After the install, you should also do a 'sudo ldconfig' although this should not keep the blocks from showing in GRC.