Created strand-based hair doesn't save / merge?

Leonides02

I'm having an incredibly difficult time having my strand-based hair move between scenes with my characters. 

I'll create the character, but then if I try to transfer ("merge") them into a new scene with their SBH, the hair doesn't come along for the ride even though it appears like it has. That is, it shows up in the scene panel and the little orange guides are there, but it doesn't render.

I've tried saving as a scene subset and as a wearable. No luck with either.

What the heck am I doing wrong?