It is a Sky-Watcher Evostar 80ED, with a 510mm focal length with the 0.85 reducer, I use with my Nikon.
My SW 9x50 Finderscope is 180mm I believe, which I use with the Zwo
Hard to know exactly. Start with some sain values and go from there. Maybe medium dither and settle below .25 pixel or so as that will be half of your imager. Then settle for 3-5 seconds.