Hi all, 

I have been working with trying to pattern flexible subassemblies and have the movements of the parent subassembly get reflected in the child, and vice versa. As far as I've been able to tell, there is a button as of SW2016 to "Synchronize movement of flexible subassembly components". Despite using this feature, I can't get my movements to link. My bottom figure represents a linear rail, the rail and slider belonging to its own subassembly. When I mirror the linear rail assembly over and slide one side, it doesn't link to the other. I feel like I am missing something simple here, or is the synchronization feature not suitable to my use case? 

Also, sorry for the poor image quality, the forum seems to be compressing my screenshots down unavoidably.
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