Cannot open shared object file
This basically means that the program is unable to locate the required shared library. If you are sure you've installed the required shared library, make sure the path to this library is in /etc/ld.so.conf or in the environment variable LD_LIBRARY_PATH. These control which directories will searched. In many cases /usr/local/lib is not one of them.
Another solution would be to reinstall the library in one of the standard library paths. In case of FOX you would do: ./configure --prefix=/usr && make && make install
