I used build/train points for my Competition Escape that never caught on... apparently too complicated for simpletons to understand the basic concepts -.-
As for timeshifting costs, I also tried finding out about that. I have found absolutely nothing, no tech, not modifying costs, nothing I have done has changed the costs.
I do have one or two last ideas that remain unpursued. And no, they are my discoveries if I want to find them! Not for you to find out about until I say so! For me to find first and actually beat nottud at finding something! *audience gasps*
So, yeah, question answered. Oh, I believe that build/train points represent how many seconds a unit takes to build/create without any upgrades. So if you modify build points to be less than the base amount (say a manor takes 40 seconds, and you mod it to -45) the building will collapse if timeshifted and possibly built (haven't tested the latter, or units yet).
Something something a quarter of a century old.