Is it okay if the starter gets runny? What if it smells bad? What if the color changes?
Runny is just fine; you can always adjust the ratio of water to flour if you need to in order to get a nice workable batter. Starter should smell good, in a strongly yeasty, beery kind of way. Not necessarily yummy-good, but never unpleasant. If there’s a rancid or bitter smell, discard the starter and make a new one. The same thing goes for dramatic color changes. A friendly reminder: Sourdough is a closed email topic.