This passage is from The Children's Bach by Helen Garner
Dexter walked with a bandy, rapid gait. They kept pace easily, not touching. They covered miles each night in the dark, sometimes heading east along the creek across the parklands to where it joined the Yarra River, sometimes north-west as far as the huge upturned saucer of Royal Park where the wild dogs in the zoo howled at the moon and monkeys gibbered behind the wall. Dexter pursed his lips and whistled a curly tune.
Dose the sentence "Dexter walked with a bandy, rapid gait." mean "Dexter had bandy legs and walked quickly"?
Does "They kept pace easily, not touching." mean "their walking speed did not changed and they walked with regular speed and this was not difficult for them"?
Is "touching" an adjective that means "difficult"?
And about the sentence "huge upturned saucer of Royal Park". Is something like a huge upturned saucer in Royal park? I searched but I found nothing. Or is the writer describing Melbourne's Royal park as a huge upturned saucer?