About rc.local: Change the version number to reflect the new installation directory, and the new binary name "lmx-server". However, I would strongly recommend to also use a logfile (-lf /PATH/lmx.log) to catch errors etc for the license server.
As for the license variable, you can edit either .bashrc in your home directory (on Linux), or use the Control Panel on Windows.
Easiest is however to run the atk_license_config utility which is provided in the most recent LM-X 4.4.2 server package (you may not have the most recent, it was updated today!) or in 13.8 (any version). The problem is actually that the old license utility from 12.2 and 12.8 had a bug which set the variable incorrectly to 6200@ if you didn't set a hostname.
Alternatively, you can just run atk_license_config (from any version) and set the license host to the actual license server hostname.