Thanks....I did something and now the mouse scrolling and everything else is working just the way it was before switching to new computer, Sierra and AC20. What I did was to open AC program first and tested the scrolling with the mouse in a blank project. It works well and then I opened my solo project [AC17] and then save my work environment to the new interface.
Lilian Seow
LEED AP | cSBA | CAPM | PMP
Interior-Architecture and BIM Management
AC20 USA | 27- macOS 10.14.6| 4 GHz Intel Core i7| 32 GB RAM | Archicad-user since 1994!