Hi, thanks for sharing this issue.
I find it a little disturbing that disposing of a form isn't closing it in the Windows 10 UI. I hope that we haven't discovered yet another Windows 10 UI bug ...
NCrunch has no real awareness of UI, it just relies on your own code to do its thing. I have a feeling that this bug is bigger than NCrunch itself, so I'm afraid that I can't provide a direct fix for the problem (you might need to take it up with MS), but I might be able to provide you with a workaround.
NCrunch has
a configuration setting that will terminate a test runner process as soon as its run has completed. This should prevent the process from sticking around after the run and allow the window to be forced closed when it terminates. If you have a long test run, it might be worth marking the test with the
Isolated attribute to force the process to terminate immediately as the test completes, rather than sticking around until the whole run is finished.
If you're performing UI testing with dialogs appearing, I highly recommend you look into
distributed processing. This will let you offload all the irritating UI testing to a different machine, keeping your development experience clean and clear. If you don't have any spare hardware to offload to, a simple VM hosted on your dev machine should still be enough to remove the interference.