Sub-assembly explode difficulty

Greetings,

I've check out SW Help and read the replies on this forum, but still can't get this to work.

"None of the selected sub-assemblies has exploded view to reuse" is what I get after selecting "Reuse Sub-assembly Explode".

Top level opened not light weight; sub-assembly clearly has parts exploded when opened separately.

What am I missing?

Thank you!

SolidworksAssemblies