On MacOS, AXE I/O is class compliant so you don't have a paperweight. However, the Control Panel is the best way to go and you should be able to download it via IK Product Manager (I had no trouble installing an AXE I/O on a new computer this weekend in this way).
However, since that's not working for you I would suggest going to My Product in your IK User Area directly via
http://www.ikmultimedia.com/userarea/my-products and downloading from there. I would also suggest opening a ticket with IK Support for direct official support from the IK team as this forum is not a medium for direct official technical support. They can surely get you up and running.