Hello!
I've added -p/--path option to fshd so that in.fshd may be started in non-standard location on a target system, when SSHD configuration forbids setting own user environment (PermitUserEnvironment no). I attach the short patch for fshd.py file (version 1.2 of FSH).
PS Do you plan to add a feature of adding port forwardings and shell access to fsh?