Same question - I know it won't run - prewash everything! I am not sure about the batting. I didn't preshrink it, but it was a quilt-as-you-go, so each block got pressed with some heavy duty steam as it was finished. Would that kind of pressing tell me what washing will do? Think the batting was a name brand available at Joannes. It wasn't the generic stuff.
I've gotta get rid of the cat hair before putting away for summer. 2 cats sleep with me at night and all 3 like the bed during the day.