Re: Robot "twitching?"
 

I see the two DIO 1's in there.

The Watchdog code isn't necessary, it's pretty circa 2009. The Safety Config took over that job.
Where are you feeding it? Unfed it will shut things down.

A double solenoid shouldn't work treated as a single solenoid, because real singles have a spring return, while doubles do not.
I'll have to try that myself at robotics tonight. Learn something new every day.

Is the first green LED on the Solenoid Module going on/off when you run your sequence? That's the best verification that your code is working.

Re: Robot "twitching?"
 

I don't know if you already did it. But all you need to do is put a "dead area". In other words what is happening is your joystick are actually sending a slight amount of value to the motors, even though they aren't pushed. So just create a code that says if joystick value is between -.1 and .1 don't move.
Hope this helps,
Alex Guckenberger