From what I have observed: rendering in a separate process means two programs running in parallel: Poser.exe and FFRender64.exe, with Poser being responsible of the application's screen. In that case, interrupting the render process seems to loose what's have already been rendered. When I uncheck "Separate process", I loose any interrupted background rendering as well, for the same reason, whatever the mode: progressive and not progressive

𝒫𝒽𝓎𝓁

---

(っ◔◡◔)っ

👿 Win11 on i9-13900K@5GHz, 64GB, RoG Strix B760F Gamng, Asus Tuf Gaming RTX 4070 OC Edition, 1 TB SSD, 6+4+8TB HD
👿 Mac Mini M2, Sequoia 15.2, 16GB, 500GB SSD
👿 Nas 10TB
👿 Poser 13 and soon 14 ❤️