specest_gui on fedora 23 64bit

[Praetorian72]

Good evening,
I've downloaded the specest toolbox from https://github.com/kit-cel/gr-specest.git
When I try to "read" data, with spec_est.gui, from an "ETTUS b200 mini", the error attached below happens. Would anybody help me, please?

$ specest_gui.py

[INFO] [UHDlinux; GNU C++ version 5.3.1 20160406 (Red Hat 5.3.1-6); Boost_105800; UHD_3.11.0.git-208-g1da86f9c]
[INFO] [B200] Detected Device: B200mini
[INFO] [B200] Operating over USB 2.
[INFO] [B200] Initialize CODEC control...
[INFO] [B200] Initialize Radio control...
[INFO] [B200] Performing register loopback test...
[INFO] [B200] pass
[INFO] [AD936X] Performing CODEC loopback test...
[INFO] [AD936X] CODEC loopback test passed
[INFO] [B200] Setting master clock rate selection to 'automatic'.
[INFO] [B200] Asking for clock rate 16.000000 MHz...
[INFO] [B200] Actually got clock rate 16.000000 MHz.
[INFO] [CORES] Performing timer loopback test...
[INFO] [CORES] Timer loopback test passed
[INFO] [B200] Asking for clock rate 32.000000 MHz...
[INFO] [B200] Actually got clock rate 32.000000 MHz.
[INFO] [CORES] Performing timer loopback test...
[INFO] [CORES] Timer loopback test passed
Traceback (most recent call last):
File "/usr/local/bin/specest_gui.py", line 660, in input_selector_text
self.fg.set_src_type(src_type)
File "/usr/local/bin/specest_gui.py", line 1036, in set_src_type
self.set_head()
File "/usr/local/bin/specest_gui.py", line 919, in set_head
self.d_uhd_subdev_spec)
File "/usr/local/bin/specest_gui.py", line 1149, in init
fg.cpu_watcher.start()
AttributeError: 'NoneType' object has no attribute 'start'
Traceback (most recent call last):
File "/usr/local/bin/specest_gui.py", line 590, in run_flow_graph
self.fg.set_head()
File "/usr/local/bin/specest_gui.py", line 915, in set_head
self.disconnect((self.head, 0), (self.decimator, 0))
File "/usr/local/lib64/python2.7/site-packages/gnuradio/gr/hier_block2.py", line 47, in wrapped
func(self, src, src_port, dst, dst_port)
File "/usr/local/lib64/python2.7/site-packages/gnuradio/gr/hier_block2.py", line 122, in disconnect
self.primitive_disconnect(*args)
File "/usr/local/lib64/python2.7/site-packages/gnuradio/gr/runtime_swig.py", line 5297, in primitive_disconnect
return _runtime_swig.top_block_sptr_primitive_disconnect(self, *args)
ValueError: cannot disconnect edge head1:0->decimator0:0, not found