When I was trying to Open Designer an error message showed up "Downloading of Launchclient.jar failed, launching will not occur." I then looked for the java folder and found that the JavaVirtueMachines folder is empty.
Do any of these posts help?
https://forum.inductiveautomation.com/search?q=Downloading%20of%20Launchclient.jar%20failed%2C%20launching%20will%20not%20occur
Forgot to mention that I installed the Ignition on Mac