Glad to hear that most of the impetus for starting the thread is on the way to resolution and/or workaround! I'll let others address the additional insights. Cheers, DanielThanks to all here for the insights and links. A lot to digest, so I'll be digging into this over the next week or so.
In any case, there was nothing anywhere about saving blocks in a library, what the library is or how it functions. It guided me to creating scenes within a preset. So the concept of swapping out entire block setups (which I'd call a "rig") eluded me. In fact, in retrospect, I think it never occurred to me because I the blocks guide is all about digging into the INDIVIDUAL blocks, not about saving them as groups... in other words, I read all that thinking in terms of the nitty gritty, which I largely glossed over because it's self evident. It didn't approach blocks as potentially being the basis of an organizational system. So this thread has opened up that option, which I think will resolve the main thrust of my goal here.