I used a workaround suggested on the VeraCrypt forums: renaming the Windows boot loader, replacing it with the VeraCrypt one, and pointing VeraCrypt at the renamed option. This meant that any Windows update that updated the boot loader would break the whole arrangement and to fix it I needed to boot from a USB stick.
I think I most recently tried on version 1.22. It does sound like this version has some relevant fixes though.
Another machine couldn't even update to 1809 without decrypting. After updating and re-encrypting, it refuses to mount any system favorite volumes. VeraCrypt is a mess. Or rather, Windows keeps breaking things.
Probably this does not even has to do with VeraCrypt: After a bit of research I found some posts. It seems like this error is caused by my SSD... I guess I have to reinstall my Windows.
Doesn't make sense to me. Cos on my laptops is running a 2015 version of windows 10. I refused to update it. Yet calculator still works there.
It's possible that you're right and mine only works cos I did a lot of firewalling.