Background info

I love Start8. I've recommended it to many people. I have it on all my 5 computers (2 desktops at each of two locations, plus a laptop).

I will be upgrading to Windows 10 as soon as I can (July 29)

As far as I can understand Windows 10's new Start menu doesn't allow hierarchical folders like Win 7 did. I have 765 start menu items in 259 folders so you can see why I badly need this!

Questions

1. Do I need to uninstall Start8 before the Win10 upgrade? What happens if I don't? Will the Win 10 upgrade fail? Will Start8 get removed by the upgrade? Or will it still work? These seem really important questions you should be publishing the answer to before July 29th.

2. Am I right about the Win 10 Start menu still not having any way to allow hierarchical folders (what were MS thinking of?)

3. After the Win 10 upgrade, should I uninstall Start8 before installing Start10?

4. With Start10 installed, is there still a way to get to the Windows 10 Start menu?

5. How many copies of Start10 do I need to buy, and can I get the discounted price for them?

Thanks.