For older devices (those devices probably will never need this license, but just in case)
 
You will need to unzip the file. 
Then go to: Settings > Configuration Files > Licenses > Install > Choose File
Here select the license.lic file
Click Install
It should tell you success.
It should be visible in the Licenses list.
 
For newer devices (FW level in the form of MXxxx.nnn.nnn or CXxxx.nnn.nnn)
 
Click on Import Configuration.
Select the .zip file.
Click Import.
It should tell you success.
You can verify by going to the SE menu and clicking on Dump VCC Debug Data.
Scroll to the end of this listing. You should see the license there.
 
You should not need this for a while. I will let you know when the latest PE release starts to require the license.
 
Also, if there is any evidence of past use of etherFAX, that MFP will never require a license.
 
I am looking at creating a java tool that would do the following for a list of devices:
  1) Update to the latest PE release or Recommended FW.
  2) Apply the license.
  3) Set Fax Transport to etherFAX.
  4) Verify HTTPS Fax Status is OK.
  5) Do a send Fax and a receive Fax.
 
Let me know if you have any questions.
