I is venting!
Yes physics is usable in unreal but its tricky pony, and stubborn one.
I am doing physics based game and its trail and error, many things just do not add up and are illogical.
for eg. i had asteroids perfectly set up for planar movement (physics constraint) they barely rotated (spinned) no matter what i did.
Then i tried to free them from constraints and add force (push them back to gameplay plane instead of constraining), but it did not work (ebil pendulum effect). All i changed was locked axis in constraint from locked Z to no locked.
So after that small experiment i locked Z axis again and removed correcting force logic. But then they started spin like mad, also sometimes disobeyed constraint.
I think they either rotated with constraint sometimes or plain broke it. Luckily i did backup right before messing with physics.
Also it is quite dangerous to add impulse or force from bp or code. it if just happens that you poke physical object right before it collides you can get quite funny glitches.
So with physics if it works do not try to make it better (without doing backup first).