Seems this issue is making itself known.
Running OSX 10.12.2 on a MacBookPro13,2 Touch bar.
Workaround suggested did not work for me.
I get the password prompt but after that, no windows just the IBM icon in the dock with the open dot beneath it.
I have left it for hours, having to force quit to exit.
Any advancements let us know!
Cheers.