I can only guess why these noodles are called glass noodles. Maybe it is because when soaked in water, they become transluscent and resemble glass.
Recipe for Sotanghon Guisado: (Updated)
2) I used rotisserie chicken from Costco and by simmering water with the chicken, broth is produced. If you have some chicken broth on hand, that is perfect, definitely use that in place of water. Sometimes I use some chicken base in paste form but it contains plenty of salt just like bouillon cubes. I'm trying to avoid too much salt in my diet nowadays.