this is my first try with Registax and I'm very confused. It does all it's supposed to but the final image come out with round areas of cross hatching. I've put up a frame but it may not show up. I've marked a few but they are all over the place.
If it is a OSC cam, I think it will be a Bayer matrix issue. I have seen it with my large OSC cams prior to stacking, or if I forget to debayer PRIOR to stacking.
You could try a different DeBayer algorithm. Cross hatching is a known problem, if that's what it is. Using a different method usually fixes the problem.