To better understand how this works, let's break down the purpose of each operator. Zen Unwrap is a multi-tool designed for quickly splitting a mesh into UV islands. Its job isn't to track orientation, scale, or other metrics, because island packing is often used right after, which would negate any calculations made for individual islands anyway. It only preserves position and scale for convenience, keeping the UV Editor clean and manageable. Once you've finished creating your islands, you move on to using other operators like Unwrap Inplace, Quadrify, Relax, and so on. The Unwrap Inplace operator belongs to a group of tools that process existing islands. It doesn't change their count—it won't split or merge them. It only modifies their shape, position, and orientation. Wanting Unwrap Inplace to behave like native Unwrap is understandable, but doing so would cause chaos and make the operator much harder to work with, as islands and seams aren't always synchronized. We can't always rely strictly on seams, which is why all Zen UV operators—except those specifically built for splitting the mesh into UV islands—always target existing islands rather than seams. Based on this and your previous questions, it looks like you're trying to build a specific pipeline. If you share what ultimate goal you're trying to achieve, I might be able to offer better recommendations on how to effectively use the addon's operators.