becuase i am stuck on this on an error (AttributeError: 'gr_hier_block2_sptr' object has no attribute 'set_callback') i decided to try to build again. when trying to install the 4fsk demodulator i get this error: make[2]: Entering directory `/home/matt/gr-fsk4/src/lib' /usr/bin/swig -c++ -fvirtual -python -modern -I/usr/local/include/gnuradio/swig -I/usr/local/include/gnuradio -module fsk4 -o fsk4.cc ../../src/lib/fsk4.i /usr/local/include/gnuradio/swig/gr_basic_block.i:26: Error: Unable to find 'pmt_swig.i' note that when i run op25 the first output line is "Imported legacy fsk4". so now i am confused as to how grc is importing the fsk4 if i cant even install it? Cheers, Matt