Yeah mine did too, up until the pedal down event that crashed the controller. In your case it looks like it might be more likely a bad interaction between the controller and SONAR. I should also mention that I was running SONAR X3 with the LX88 and the Control Surface Plugin per
these instructions. I have not tried the CS plugin with Platinum yet.
I think that there may be a way to configure Midi-Ox to run as a pass-through monitor while you have the LX88 and SONAR up and running (though I'm not totally sure - it's been a long while since I attempted something like that). If so, it could be interesting and/or useful to see (and log) what's going on at the point when SONAR crashes. Maybe it could help steer your investigation and give you more ammo to whomever you report the issue.