I have collected some rain lily seeds.  Habranthus tubispathus (Rio grande copperlily).  I understand they are best planted fresh.  If I show them now would the seedlings over winter?  Or can I store them for spring?  I'm in zone 8b. Ideas?  Thanks so much.

if they are growing wild in your area, I would expect them to do fine through the winter, whether they germinate or not, since this would be their natural method of reproduction. But if you start them in a pot, you will want to sink the pot into the soil to mitigate mitigating temperature variation. (The soil will never get as cold as the air does through the winter.)