Fallout NV seems to work fine after upgrading my computer to Windows 10, but . . .

When I launch Pipboy only some of the functions are accessible.

Data is fully working

For STAT and the middle button only the first tab is accessible, meaning I'm stuck with Weapons and Status Tabs. It's not possible to activate S.P.E.C.I.A.L. oder cloth or something else. Also there is no audio/video feedback when the cursor is hovering over other tabs. There is no problem with the Data tab. All functions are selectable.

Needless to say that this results in an unplayable game

Any hint?

ALot of people seem to be jumping right into this upgrade. I advise the best option is to dual boot Windows 10 at this point.

Does this happen in a new game or previous save?

It's a previous save. In the meantime I found out that I can use the keyboard's cursor keys instead of the mouse. Working with "ESC", switching between Stat, Data etc und trying the cursor keys helped me out, so far. Not a very nice handling, but at least the game is playable.