While starting via terminal LicenseManager.Console which is by default located at /opt/ABBYY/FREngine12/Bin it may appear message of the next context:
"Error while loading shared libraries: libFineObj.so: cannot open shared object file: No such file or directory."
This is most probably caused by the absence of LD_LIBRARY_PATH variable value.
To fix it, run the next command for FRE12 in the terminal:
For FRE11 the command will be next:
For now, you should be able to run LicenseManager.Console and activate/deactivate the FineReader Engine license.