If the Chromebook uses x86 CPU architecture it might work, but I've no idea if the specs are good enough. The chmod command just sets file permissions, and the +x option means make it executable (so you can run it as a program). There shouldn't be any output from the command. But you should now be able to launch the program - i.e. double click the icon or type:
./Digital-Logic-Sim.x86_64