...
Failed to create restart thread errno=12 in cgminer.c restart_threads():5063
... It was up to being the 229th device in cgminer. ...
It's unhealthy for that number to continually climb.
The system will eventually prevent new resources from being allocated..
Get the other devices going in its own cgminer with command line option --usb :1, (or total devices - 1) while you work on that last one.
As i mentioned a couple of post back, it would be better to test/tune it isolated.