- Yes, all recent releases of QlikView (11.20, 12.xx) are compatible with Windows 10. See the System Requirements document.
- Yes, there are known issues. See the Release Notes that accompany the particular QlikView version you are using. It has a separate section on "known issues".
- Yes there are bugs. QklikView is complex software made by humans. Bugs are reported almost every day. If you want to know which bugs are still unresolved, contact Qlik Support and present your problem(s) to them. Don't forget to mention which version (including SR number) you are using.
Concur with information Peter provided. Depending upon the version of QlikView, you need to check the system requirements.
If you are unable to access the Qlik Support Portal, then you'll need to work with Qlik Customer Support. They will be able to assist you in ensuring you have access to the portal.
Hope this helps,