i just set up HA a few days ago and got my z stick and a few switches yesterday. I have a z-stick gen5, raspi b+ and hasspian image. I read a bunch of the forums and made 2 changes to get it to work.
first
sudo su -s /bin/bash homeassistant
vi /srv/homeassistant/pyvenv.cfg
then on this line “include-system-site-packages = true” i changed false to true. it did not fix the issue, so i don;t know if it was neccessary.
second;
edit /etc/group and add homeassistant user to dialup group, should look like this “dialout:x:20:pi,homeassistant” as you can see below, you need to be root or in dial group to access zstick.
pi@raspberrypi:~ $ ls -l /dev/ttyACM0
crw-rw---- 1 root dialout 166, 0 Jan 15 12:36 /dev/ttyACM0
i set up my first switch to go on/off with sun an it worked last night and this morning!