arm doesn't connect to UNIX domain ControlPort with cookie authentication

There is nothing in the man page about this. It seemed like ~/.arm/armrc should have helped but this armrc:

DataDirectory /var/tmp/tor/data ControlSocket /var/tmp/tor/ctrl CookieAuthentication 1 CookieAuthFile /var/tmp/tor/data/control_auth_cookie

doesn't make arm connect, and it still asks for the passwod.

Command line should support this. Natural syntax would be: -i /var/tmp/tor/ctrl:/var/tmp/tor/data/control_auth_cookie

To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information