Is the new trail open, now?? This is one I‘ve been looking at doing his summer. I might just have to go Sunday or Monday. Also, is sleeping in your car allowed at the TH??

Trail is as shown on the "West Slopes" route page for Mt. Columbia, nicely graded switchbacks have been constructed from leaving treeline to about 13.3k, from what I can tell that is the extent of the "new trail". Signs at the trailhead say no camping, there are plenty of good dispersed spots along the road leading up to the trailhead proper, some within easy walking distance.