I've had the same problem from time to time. For me, it never stops. I have to use Task Manager to End the Cakewalk task.
The other difference for me is that I am still able to go into the File menu or the Edit menu.
I can even open another project. And if I do, the Now time continues to proceed even though the Now line is stationary.
I was finally able to get it to stop by changing the configuration settings (while it was running) to Stop if Dropout.
Then I changed my ASIO buffers to 32 (to cause the dropout).
Reviewing the device settings I remembered that "Plug-In Load Balancing" doesn't work on my system.
Un-checking that box got it working again.
HTH,
Steven