A crash with Windows 10 has been discussed in
https://www.mobileread.com/forums/sh...d.php?t=280049. No real idea why. It seems to be related to USB3 ports but lots of people are using these and not seeing a crash. There is a workaround or two in the thread.
For the Kobo desktop application problem, is that after the PC crash? Or does it happen after a clean setup? The other reports are this was OK.
My usual first suggestions for these sort of problems is try another PC and do a factory reset. If that doesn't solve it, and it is a new device, it suggests that it is a faulty device and I would recommend exchanging it. For an device that has been in use for a while, I don't know what to suggest.