I checked libpar2 from Suse-repository and it is not OK. The "libsigc++" was compiled into "libpar2" instead of be linked as a shared library (this is wrong).
Download the correct version of libpar2 from "http://sourceforge.net/project/showfile ... _id=390591" -
Unpack rmp (probably few times) until you get a file "libpar2.so.0.0.1", then replace the existing file in "usr/lib" with an unpacked file. You can also try to just install th rpm, but I'm not sure if it will accepted by your package-manager.
Then try "ldd /usr/lib/libpar2.so.0"; it should print "libsigc-2.0.so.0" in dependencies now.
If "ldd /usr/lib/libpar2.so.0" works, you can make nzbget.
If it not helps you need to build and install libpar2 from source code.