Okay, METADATA with ParallelAccelerator verison 0.2 has been merged so if you do a standard Pkg.add() or update() you should get the latest version.
For native threads, please note that we've identified some issues with reductions and stencils that have been fixed and we will shortly be released in version 0.2.1. I will post here again when that release takes place. Again, please give it a try and report back with experiences or file bugs. thanks! Todd