After a bit of testing it seems to be on the RPi that the problem exists.
Running it off my Kubuntu desktop it seems to respond correctly (relative position count changes in indi control panel when focusing in or out).
I use a Usb_focus, not a Hitech but I get a similar problem on a slow computer.
For me the problem is the driver pooling the device too frequently, this make some random error with wrong position reading and sometime the focuser moving far from the requested position.
I solved the problem by increasing the value of POLLMS from 250 to 1000 in usbfocusv3.cpp, making the position to refresh only every seconds.
In hitecastrodcfocuser.cpp the value of POLLMS is 100. Maybe increasing this value can also help you.
I can't seem to find the updated driver for the focuser.
sudo apt-get update then install doesn't seem to have any new versions available.
(I can't use the s/w updater from MATE on rpi as it complains about lack of disk space)
Having almost given up running this from the rpi I've rebuild my desktop to run as the Indi server with Kstars and Ekos.
All running well apart from (you guessed it) the Hitec DC focuser. The driver crashes when started.
Hi Jaseem, I guess the update hasn't worked it's way through yet as I haven't seen a fixed driver yet.
I have a workaround for now (on Kubuntu 16.04) which entailed deleting the config file and editing the default config and loading that manually each time I start INDI.
Yes that was what fixed it, so it's been long in the INDI repo. You can ignore the CI error, that was temporary. Maybe try to run with sudo apt-get -y dist-upgrade