from my post here...
Box Community
This is absolutely not supported by Box, don't take chances if you are not willing to take the consequences for this. That said, I felt the only problem with Box Drive was that it was using an older incompatible version of osxfuse, so a simple drop-in replacement was all that was needed.
Install the latest osxfuse from https://osxfuse.github.io (I used Pacifist to install to get around the macOS version check)
Install the latest Box Drive (quit out after the errors)
Trash /Library/Filesystems/box.fuse
Duplicate osxfuse.fs (select to highlight the file , press command-D)
Rename the osxfuse copy.fs to box.fs
Launch Box.app (Box Drive, in fact uninstall Box Sync as Box claims incompatibilities)
Enjoy!
In 2 days of usage, I haven't seen any issues so far, other than some file incompatibilities that I web uploaded.