Updated Crown Molding Pack, v 3.3.0. https://superhivemarket.com/products/crown-molding-pack Wayyyy better auto-rotate behavior. This one was the "I'll never figure this out" math that I thankfully did, in fact, figure out. The add-on/extension now determines the face's normal, un-rotates the curve from that orientation to flat on Z, applies the curve rotation, and finally re-rotates the curve to match what it was. All this to make 3D curves work better!