Hi!
To answer your questions:
1) global
2) both
3) in game ver. 1.1 unused social production will be diverted to military, and unused military will be transfered back to pool. In game ver.1.0x unused social production will be charged, and lost
4) nope. You can only focus spending
5) pop only provides money and troops (and scores for metaverse)
6) set % effect, nothing else.
7) vague. The formula is complicated. AFAIK there'nothing you can do besides what you wrote.
8) no
9) depends on approach. I avoid having very specialized production and research planets
10) you buy missing production, paying ~10 times the costs of regular production. Avoid that on colonies, or you'll run out of money very soon.

HTH.

BR, Iztok

yes, but on the rush buildings, things like rushing your factories into being helps a lot becuse it lessens the time it will take for subsecuwrnt projects. i.e., you just started a flegling colony, so first thing you do is build a factory( of course), then what ever you want on however many tiles there happens to be open at the time; if you rush your first factory, then you cut the time it would have cost in weeks by half, and perhaps half per each additonal factory you build while you are currently building, say, a large project or a tech. center doing that quickly adds up.