Well I wouldn't have guessed that a self-styled 'Windows' program would use Unix conventions.
How do you want to transform unix style paths to windows style?
I couldn't find any help on the supported 'Dos' commands, so I guess you only get that help from a Unix system.
You cannot expect any help. WinSCP simply passes the command to the server. It does not interpret, nor understand it in any way. So it supports commands that the remote side supports, which differs.