Hey there,
I just tested Unity with my windows 10 VM, what seems to happen is in unity mode it think windows explorer should be showing . it shows the desktop in an an explorer window. The task bar icons still show up, I didn't try the applications menu because like i said I don't use Unity hardly ever because i want the full OS experience like it would be on a physical computer. With that said, I think unity is working correctly, but because3 how windows 10 manages the desktop, it confuses unity into thinking applications should be shown that really shouldn't because it's different then traditional windows. Windows 8/8.1 were different because the live tiles and desktop weren't combined into one interface e.g. it didn't have a separate desktop vs tablet mode it was the same on all devices. So it looks like fusion simply needs to be updated to take that into account.