You can get a list of all commands by simply typing in windscribe --help at the commandline.
You'd change locations by first typing in windscribe locations and then typing in windscribe connect "location name" (location name should be in quotes for server names with more than one word).
Also, windscribe viewlog will allow you to see the latest logfile, and windscribe sendlog will let you send it in to us.
Please be aware that development on the CLI app has been halted and it may not function with certain newer distros.