Download the package fro your architecture:

Downloads: GammaScoutTools-1.0.2-1.x86_64 1.0.2-1 HOT Open Source tools for reading data from Gamma Scout geiger counter  GNU/GPL ;Francesco Teodori Website Friday, 27 September 2013 10:07   Apple iOS  65.6 KB  779 Download

GammaScoutTools-1.0.2-1.i586 1.0.2-1 HOT Open Source tools for reading data from Gamma Scout geiger counter  GNU/GPL ;Francesco Teodori Website Friday, 27 September 2013 10:07   Apple iOS  64.82 KB  760 Download

Before installing the package, add the science repo and install python-sip-bin available there. Add the python3 repo and install python3-pyserial and the other needed python3 packages. In order to solve some API compatibility issues I repackaged the python3-qt4 rpms:

python3-qt4-4.10-117.1.x86_64 4.10-117.1 HOT PyQt - python bindings for Qt 4  GNU/GPL ;Francesco Teodori Wednesday, 10 July 2013 12:50   Apple iOS  19.63 MB  757 Download

python3-qt4-devel-4.10-117.1.x86_64 4.10-117.1 HOT PyQt - devel part of python bindings for Qt 4.  GNU/GPL ;Francesco Teodori Wednesday, 10 July 2013 12:50   Apple iOS  8.38 MB  807 Download

python3-qt4-4.10-117.1.i586 4.10-117.1 HOT PyQt - python bindings for Qt 4  GNU/GPL ;Francesco Teodori Wednesday, 10 July 2013 12:50   Apple iOS  19.03 MB  789 Download

python3-qt4-devel-4.10-117.1.i586 4.10-117.1 HOT PyQt - devel part of python bindings for Qt 4 ;Francesco Teodori Wednesday, 10 July 2013 12:50   Apple iOS  8.37 MB  756 Download

If needed install these packages instead of the ones coming from the python3 repository. After the latest updates, this issue seems to be solved. After installing the package, add yourself to the dialout group.