This is a long shot but might be worth checking. Is your installation 64bit i.e. x64? With this latest update, and for the first time ever, CCC had verbose install enabled. I notice it had 32bit Platinum chosen by default. I always install 64 bit. If verbose install was disabled, I would not have known.
 
Could the 32bit version cause the problems people are having?
 
Cheers, Peter.
 

I'm having some issues as well. Every time I open a project I've been working on, I'll get the plt stops working crash. However, each time I restart the project, it's all good.
 
The other day, I too inserted CA-2A in Prochannel FX bin and got the dreaded spit/meltdown issue which had been okay. I also inserted a wave plug-in on the bus and the same thing occurred...big noise through my monitors, red-lined input, horrendous noise. I have to immediately turn down my monitors, save my project and restart...then it's all good...weird and really annoying as it puts a halt to my work and doesn't do my monitors any good I'm sure. I have a work-around now where I'll turn down my monitors each time before inserting a plug-in. 
 
No magical system auto fixes here unfortunately. 

Bristol_Jonesey

soens
Dumb question: Are the updates cumulative? If so, do you inherit the bugs from the last update with the next one?

Updates are indeed cumulative but that's not to say any given bug wasn't eliminated prior to releasing a new update, otherwise no bugs would ever be squashed!

I ask because if I choose to pass on this update but go with the next one because it has something I like/need/want, I could end up with a bug I tried to avoid that wasn't fixed.

Fabio Rubato
I'm having some issues as well. Every time I open a project I've been working on, I'll get the plt stops working crash. However, each time I restart the project, it's all good.

Same here, but here's what's REALLY interesting: I had this happen on my desktop computer (which always lags my laptop by a few weeks) with 2016.10, not 2016.11 - but only right after a Windows update. 
 
I also started having an issue where my monitor didn't open at the right resolution. There's a lady in Gibson's graphics department who had the same problem; I asked if she knew of a fix but said it happened with the last Windows update and she has to edit the resolution after opening (which is what I have to do as well).
 
I think Ampfixer is spot-on about "too many variables." I'm seeing the same thing happen with the forced MacOS updates (if you know any Final Cut Pro users, ask them about what happened with the last update - some of them will say things that will truly expand your vocabulary of cuss words). Frankly, I think both Microsoft and Apple could learn a thing or two from Cakewalk, specifically rollbacks and quick hot fixes.

This is all  very true, however my studio PC is on an isolated network not connected to the Internet.  I connect and run Windows updates at times of my choosing. I have not updated windows in the last 2 months and still had issues with the last Sonar update. Short of there being a crucial recent update (I am runnig WU as we speak) the windows update variable doesn't apply. Sometimes it's just Sonar. I couldn't count the number of times I have had issues over the years where all kinds of windows update solutions/causes were suggested that I spent many hours trying to no avail, but after a further Sonar update/fix release all was well:)
 
Computers are a fickle world of infinite variables, but I do find a little patience often trumps speculation:)

the last time i let windows 10 update or check for updates was 31st of july, i'm still on v1511, i am not having any issues with stuff mentioned here or in other threads. had a slight hiccup on first installing the latest platinum update, but that was cured, or disappeared after a reboot.

I did have a problem after this last upgrade with one project.  When I tried to open it from the start screen, Platinum would stop working, give me the microsoft error message and shut down.  This happened a couple of times in a row.  I started Sonar again and opened a different project and everything was fine.  I again tried to open the project that initially caused the problem and the same crash occurred.  After restarting Sonar, I closed the Start window and tried to open the problem project from the file menu.  This time it opened fine.  I did some work on the project, saved it and closed the program and shut down the computer. The next time I started, attempting to open that project from the start screen again caused the crash.  I restarted Sonar, opened the project from the file menu and saved it under a different file name.  Thus far, I have been able to open the renamed project from the start screen without a problem.

RonCaird
I did have a problem after this last upgrade with one project.  When I tried to open it from the start screen, Platinum would stop working, give me the microsoft error message and shut down.  This happened a couple of times in a row.  I started Sonar again and opened a different project and everything was fine.  I again tried to open the project that initially caused the problem and the same crash occurred.  After restarting Sonar, I closed the Start window and tried to open the problem project from the file menu.  This time it opened fine.  I did some work on the project, saved it and closed the program and shut down the computer. The next time I started, attempting to open that project from the start screen again caused the crash.  I restarted Sonar, opened the project from the file menu and saved it under a different file name.  Thus far, I have been able to open the renamed project from the start screen without a problem.

I've had that same thing happen as well...and before this last update.

The "synth tab missing" is the only problem I've had so far as well Jonesey. Had to open it via Views > Synth Rack View as well or press "o" to display the synth rack.

It's not the first time i had troubles with some new updates. Expecially with 2016.10, I had to roll back to 2016.09.
With november update I had some "Sonarplt.exe has stopped" all related to plugins like Melodyne, AD2 and TH3. But I've found that with every start of Sonar things become better and better. Now everyting is all right.
I think that these issues originate from Windows, that at the first starts of Sonar's new updates is fighting to stabilize the daw.