I just tested this with bombs and it works fine but I do find I need to face the steerpoint before I SP.
So I switch to AG, do CCRP, TGP on left MFD, HUD as SOI still ... not sure if its placebo but now I move the pointer from steerpoint around to see if it works OK, then I click SP and SP again to deselect and pointer jumps to center of HUD and it moves with the jet.
Now couple of times it didnt work when I started to do other things first, like targetting etc. so to fix it, I faced the steer point again, made TGP SOI, selected a point track, then deselected using the sensor down or whatever is the key to release the lock , and after that click SP 2 times again, that would bring it to snowplow. This is when facing the steer point (I usually click back and forth on the rocker switch to make steerpoint the current target so I know im facing it)
Made a quick video just for the CCRP snowplow: