GD on can pink frame older cameras, + do what you see. I do the best of both worlds and turn it off while recording. You can try reducing the # of indicators, check CPU usage see how high it is. 20-30% may be ok, 60-90% will probably give you bad frames.
I have later builds too, lol.
For the LV in dslr controller, etc. Does 50D even support this function without raw? Its pretty old, I'd compare with 5DII.