Hi Mät,
This is a machine-specific issue that cannot be reproduced under normal working conditions, on any supported platform. My advice when things like these happen is a performing a complete reinstall of Windows 10, trying to achieve the cleanest possible configuration without any vendor-provided utilities (bloatware).
On my secondary OS (Ubuntu) the software runs fine. However I would prefer working on Windows.
Interesting. The reference implementation of PixInsight is the Linux version, where you'll get the best performance and reliability by far. Soon we'll have a FreeBSD 1.8.6 version, which will be equally stable (if not more) and with similar performance levels.