Is a limp/gait abnormality in a woman a turnoff?

It's an old instinct from prehistory. Humans, like any animal, would seek out the healthiest specimens to mate with, because the world was dark and dangerous, so you had to maximise the chance of survival and of having healthy children who would also survive. There's still elements of that evolutionary habit in our DNA, but we've intellectually suppressed that trait to appreciate other fine aspects of a human being. Indeed, your own positive attitude to life and your intelligence will overcome any negative attitude towards your physical aspects.