Hi,
We cannot reproduce these problems. I have a Windows 10 machine running PixInsight 1.8.4.1195 since today at 8:00 (it's 17:45 here now), doing all types of dynamic operations (DBE, DynamicCrop, CloneStamp, DynamicPSF) on large images, saving projects, loading projects, etc, with absolutely no problems. The machine is a 27" iMac 5K running Windows 10 on a BootCamp partition.
The fact that this happens on two machines is potentially very helpful: just find some relevant property shared by both machines, and you have found a useful pattern. For example, do both machines use the same antivirus or firewall application? Some utility application running on the background? The same video drivers?
I assume you're running the latest 1.8.4.1195 version of PixInsight. I also assume that you haven't installed any unofficial modules (otherwise, we may know what happens). I have two general suggestions:
1. Although it's unlikely, this could be an issue with the OpenGL implementation provided by your video drivers. Run PixInsight with the following command-line arguments:
"C:\Program Files\PixInsight\bin\PixInsight.exe" --opengl=raster
If this does not help, try with the following:
"C:\Program Files\PixInsight\bin\PixInsight.exe" --opengl=software
To run these commands, right-click on your Start button and select Run. Then enter one of the above commands and click OK.
2. Make a good backup of your data, then perform a clean installation of Windows 10. Don't install anything besides Windows and PixInsight. If the application works well now, then we have a software conflict. You can proceed step-by-step installing the rest of your software, and see if PixInsight starts causing problems again after one of them.
Let me know if this helps.