Wow! I knew it wouldn't be easy, but...
Thank you for the replies.
I use 'skybox' as a way of describing the intent and potential complexity. I'm really targeting SandBox users--to help pack up projects and clean up after themselves.
You've pointed me at some big problems, and I'm already glad I didn't spend hours working on this already. If this were baseball, I'd say its a ball and 3 strikes:
1. I see that I can't script [object puts self back into inventory] So the user would have to pack up, then pick up the box and TAKE it, in two steps. That's not too onerous. (call it a 'ball' and not a 'strike'.)
2. I'm not hung up on 'linking' in the traditional LSL sense. I simply wanted a way to collect a set of objects via program control. Only relative physical position would be important. The objects would not need to be aware of each other. Already linked items need to maintain their relationships. I guess I'm after a 'Group/Ungroup' like command.
I'll
read up on Builders Buddy. Its's
close, in that it does the rebuild. The time I used it, I found the setup to be tiresome--that's the part that I'd like to automate. (1-1)
3. ewwww. Mixed permissions. That could be a problem. Since all objects would be [legitimately] owned by the skybox owner, and the skybox would be nocopy, no transfer, I'd assumed away the permissions issues. But I see now that
putting NOCOPY items into the box would be problematic. more
reading. (1-2)
4. Phantom items are an issue?

I did not know that. I should have
read more. (1-3 and I'm struck out)
Thanks for the feedback and the batting lesson. /me heads back to the Wiki and the Forums.