My space colonists have found a home in the ring system of a (maybe chthonian) gas giant. The rings are based on Saturn's in terms of appearance, but can they be made of gases or liquid (maybe droplets) instead of rocks? I know it doesn't sound right since rings are made of solid materials, but I know similar structures exist out of gas and plasma (plasma torus).
Rings containing gas are actually studied as part of planet formation. This causes fluid-dynamic effects such as drag. So, the gas ring is short lived, and meanwhile interacts with the solid bodies.
That's "short" on a geologic scale though. If the conditions hold for a few thosand years, people might decide to move in.
So how can this be? Answer: it's recent. Take a look at Saturn, which you mentioned, for further inspiration. When the inner moons are demolished you get an extended debris field for a (geologically short, human long) time before reforming into fresh moons and short-lived rings. This happened most recently 115 million years ago.
Now your system is not Saturn, but different. The moons can be made to contain lots of water, and orbital instability causes a chain reaction that shreds them... and something else about the planet or the star somehow makes it warm enough to make a vapor ring, or liquid moonlets that stay heated rather than freezing, or something.
Hey, how about a pulsar? The old sun might "microwave" liquid water to keep it not frozen, even after it blew the gas off the original gas giant. Maybe it's a magnitar, and the re-forming of the planetary system after the supernova could cause the chtonian reminent to migrate inwards, as forming planets do in new systems.
So the intense magnetic field of the pulsar and the iron planet keep moonlets and dust in a tight orbit along with gas that doesn't dispurse because its angular momentum can't go anywhere (handwaving... it's sheaparded to remain stable). And, it stays nice and warm, in the liquid-water region.
So, Nivin's Smoke Ring in miniature, with pulsar planets.