Well, the story of FileSystemInfo is a bit complicated.
Long time ago, Tom's idea was that it will allow unified handling of virtual filesystem. Practical example at the time was building something at remote machine with theide - Tom was using theide in windows to drive simple utility program on Solaris (over TCP/IP).
Anyway, that appears to be the last such use, so today I am using it just to identify the type of disks in FileSel on the local filesystem.
Similar issue is AProcess as the virtual base of LocalProcess....
Today, I would guess it is easier to setup shared filesystem and compile umk on target platform.