Gremsy gStabi H3 doesn't Match Manual and "Lock" function from Transmitter?

I have a question about my Gremsy gStabi H3... It doesn't have any CAN port like instructions show.   How do I use CanLink or other Can options?  Also, is there a way to program on the transmitter to set a channel on transmitter to "lock" (like in app) in other words, to return the gimbal to facing front, like a home position?  Sometimes flying the H3 on my multirotor, I forget which way the camera is facing and would like ot be able ot flip a switch and have it return to front facing.