I can sympathize with your worry of course, but small poop is an observandum, not a harbinger of death. It means she has eaten less fiber than she should. y Bam gets small poop sometimes. Hay and water are the best things for this. If you can get fresh clean grass (no pesticides or raccoon poop) it’s just as good as hay but often a lot more popular (give sparingly if she’s not used to fresh grass). To get her better hydrated, a small amount of leafy veggies dipped in water can be given.
As for the papaya, rabbits are well known to refuse food the first time(s) it’s served to them. My Yohio was terrified the first time I served him a slice of banana, he wanted absolutely nothing to do with it. Another member’s bun freaked out when he was presented with a strawberry. It’s within the scope of normal rabbit behavior. They usually try it the third time or so. Is she willing to take other treats that she normally loves?
You can give simethicone gas drops if you suspect gas. It can also have a bit of a lubricating effect. It’s not taken up by the body, but gets pooped out. It’s still of as baby gas drops at for example Walmart.
Exercise is important for the workings of the intestines and a light tummy massage can also be helpful. Here’s a great video on how to massage your rabbit: http://youtu.be/JnuxGLa2reg