Mac Client: Cannot launch game after update (Unhandled Exception)

Client launches to the Lodestone / Login window. Enter name, password, and one-time password. Client updates; PLAY button appears. Click play. Screen goes blank briefly (like monitor syncing), then full-screen black with a live mouse cursor. Window pops up:

Exception Raised
Unhanded division by zero at address 0x776c08c4.
Would you like to create a crash report?

I click yes and the screen changes: I now have a menubar along the top with basic FFXIV options, live mouse cursor, black screen. As far as I can see no crash report is generated. I can choose to quit application from the menu or from the dock, but app refuses to exit and I have to force-quit.

Game was working until hotfixes this morning (6/16). Restored backup of older client version and tried updating again with same results.

Please advise. :)