Right now I'm running X3c.
 
Things I would consider looking at if I were the OP:
 
1. First check what versions of the plugins you're running. I just looked and my VTM is version 1.0.1.1 (build 5065). My VCC is 1.5.2 (build 2301). Both are the 64bit VST2 versions.
A) If you're running older versions, try upgrading.
B) If you're running newer versions, try downgrading. 
 
If you're running the same versions as I am....
 
2. Create a project that contains only audio tracks (no instruments), and Slate's VCC and VTM plugins (no other plugins). Does it crash on load? Try a few times.
A) If yes, then it's gotta be system related somehow (could be a video card issue, outdated graphics library, who knows). This will make it difficult to diagnose.
B) If no, and you can consistently load the project without crashes, try looking at what other plugins are in the projects that crash. Introduce new plugins one at a time and test a few project loads to make sure each works, before adding another. I wouldn't be surprised if there was some incompatibility between VCC/VTM and some other instrument or effect. Example: maybe VCC and VTM don't play nice with Session Drummer, which would explain why Cakewalk has so many reports of problems, and I never do because I don't use Session Drummer.

This just in from Mr Slate himself, or whomever runs his personal Facebook page:

"Hi Ludwig, VCC will be ported soon to our new framework and bugs will be fixed."
 
 
 
Bob, thanks for YOUR offer too - I'm in too deep with my mixes, and the bugs go back to early versions of X2 or X1. I reinstalled VCC only using the 64bit option, and it seems MARGINALLY more stable, for whatever reason, provided I adhere to a few odd workarounds (like don't click on the console view until you have opened some buss plugs in the Bus view etc). I'll persist on this course for now. Thanks for listening guys. And please know I am a huge defender for all things Sonar, in a land ruled by Mac-based DAWs. :O)

Let's hope you get this sorted soon, LJB.
 
I, too, live outside North America, and so have to rely on Email support, which can be a little s  l  o  w..
 
I have found Cake's support on this forum remarkable, though. Many times I have found help by either posting on here, or  by P.M-ing Cake staff.
 
This forum, and Cake's customer service, are a major selling point for Sonar, as far as I'm concerned.

Cool beans.
 
I am quite pleased that the Cakewalk folks and third-party developers are so eager to work things out.  I get this sense that the X3 release is truly something special, and it seems like lots of good things are coming together with this, and it is and looks to continue to be a really really cool thing for all.
 
Bob Bone
 

LJB
This just in from Mr Slate himself, or whomever runs his personal Facebook page:

"Hi Ludwig, VCC will be ported soon to our new framework and bugs will be fixed."
 
 
 
Bob, thanks for YOUR offer too - I'm in too deep with my mixes, and the bugs go back to early versions of X2 or X1. I reinstalled VCC only using the 64bit option, and it seems MARGINALLY more stable, for whatever reason, provided I adhere to a few odd workarounds (like don't click on the console view until you have opened some buss plugs in the Bus view etc). I'll persist on this course for now. Thanks for listening guys. And please know I am a huge defender for all things Sonar, in a land ruled by Mac-based DAWs. :O)

I was just fixing to say that all his plugs are supposed to be updated soon. A couple already have. I hope everything gets worked out for you. Hang in there!

bitflipper
I don't want to aggravate your aggravation, Ludwig, but an unhandled exception raised by a DLL is more likely to be an issue within the plugin rather than the host.

unless it' was working great in version A and not version B of the daw ;)
 
had the isssue with VBC ...rolled back to X1 ...wating patiently ..X3 rocks but has been dangerous ....for me ..

LJB
This just in from Mr Slate himself, or whomever runs his personal Facebook page:

"Hi Ludwig, VCC will be ported soon to our new framework and bugs will be fixed."
 
 
 
Bob, thanks for YOUR offer too - I'm in too deep with my mixes, and the bugs go back to early versions of X2 or X1. I reinstalled VCC only using the 64bit option, and it seems MARGINALLY more stable, for whatever reason, provided I adhere to a few odd workarounds (like don't click on the console view until you have opened some buss plugs in the Bus view etc). I'll persist on this course for now. Thanks for listening guys. And please know I am a huge defender for all things Sonar, in a land ruled by Mac-based DAWs. :O)

 
tell slate that VBC has issues as well (at least on my system ) ...it was working great X3 B and no more X3C (VBC fg grey only ..weird ) so new framework isn't a waranty....some happened (in the plugin maganement) from X3B to X3C , would love to know what 

Gee, I am surprised reading this thread.  I honestly didn't think you, Ludwig, had any sense of humility from what I've read in your previous posts.  I guess the better comes around eventually.
 
Good luck!
 
Kind regards,
 
Living Room Rocker

LRL, not sure how to take your comment, so I'll just acknowledge that I received it. Thanks for the "Good Luck".
 
I will add this - if you are implying that I am arrogant, or an a-hole, because I demand a product that I paid good money for (in advance) to work, then hey, I'll gladly wear that moniker, and also the one that says Consumer Rights.
 
I'd like to remind you that I don't escalate anything unless it's a real problem, and I always follow the proper communication lines first. I have all the communication datiing back to speaking to Brendon about this to prove that.
 
When it's fixed, at least you'll also enjoy the benefits of a better system.

Whoa, dude!  Take a little step back.  I am not at all implying you are arrogant because you demand a product that you paid good money for...  Anyone here making an invest has expectations.  Totally natural, totally normal.  You certainly don't need to remind me of the history here or your efforts toward a resolution.  But, man, that tone speaks volumes.
 
Thanks for happy prospects, but I don't rely on Slate's plugins myself.
 
Kind regards,
 
Living Room Rocker