Disappointing Ha result on Pacman

There's so many things wrong with this image, that I really hesitate to post it, but need to improve so would appreciate any kindly advice. I don't really do Ha (perhaps that should be "really don't do Ha") but it was a full moon last night, and I had just put everything back into the observatory after being away on holiday (to France, yes, very nice, thanks.) So nothing was tweaked in any way, but I wanted to see if everything basically worked. Setup is: Quattro 200mm reflector

Here's the guide log in question... There is 10 minutes between each dither, and the vertical scale is +/- 20". Is it conceivably a cable dragging? I've tried to tidy up everything as much as possible. I'm using an Eagle2 attached to the RA arm of the M-Uno mount as a sort of counterweight, but there still has to be one cable, the power, going to it. In fact, there's also the lightweight cable for the manual guide controls which goes to the mount. Balance is really quite good