Are there any instructions out there for getting a shared folder to work on GhostBSD VirtualBox guest? I have a Windows 10 host and have a folder on my desktop that I would like to be able to use on my VirtualBox guest. Please advise. Thanks.

GhostBSD is based on FreeBSD. FreeBSD is not supported as guest.
See also: https://forums.freebsd.org/threads/virt ... der.12436/