2.  (UI bug) Planet bar's Approval of "100%" can be a false positive for Approval bonus tier of +40%.

Nomenclature: The Planet bar is in the lower left corner.  The Planets list is the right edge column.

• Approval bonus tier +50% occurs at Approval 100%.  For this tier, both Planet bar and Planets list show " 100%".
• Approval bonus tier +40% occurs at Approval [95,99]%, where the square brackets are math notation for a closed interval.  For this tier:
• Planets list always shows " 99%" (or less)
• Planet bar can sometimes show a false positive for " 100%".  (In this case, the bar contradicts the list.)

This makes the Planet bar unreliable when you're pixel-searching in the Govern wheel to optimize a planet's Approval.

Work-arounds:

1. For every planet, if it shows " 100%", hover over its Approval bonus until the tooltip pops up.  (This majorly sucks.)
2. In the Govern wheel, click wealth-ward until the Planet bar first shows " 100%".  Disbelieve it, and keep clicking upward by pixels until your "bc%" wealth axis setting increases by an extra 1% wealth-ward.  (i.e. if it shows the false positive at wealth 21%, then keep clicking until you get to wealth 22%.)
3. Govern from the galaxy screen (not from the Planet screen), so that you can see the Planets list in the background.  It is reliable (whew), and it updates per click.
4. To micro-optimize your empire's Approval, once per turn, sweep your eye down the Planets list's "" column, and look for the 99s.

I do #2 - #4.  I've learned to cease #1; I just do #3 instead.

4.  (Roundoff error) Finish colonizer from afar to "teleport" civilians for free

Screenshots to follow (when I set it up again).

Outline: This seems to be a cascade of several inconsistencies in shipyard management.  But it works.

• A shipyard can have 1+ sponsors, at any distance.
• A sponsor at range 6 hexes or closer delivers full mps (zero penalty).
• A sponsor at range 7+ hexes gets a progressively larger mp penalty.
• Every sponsor always contributes at least 1.0 mp minimum, regardless of its distance and its mp% wheel setting.
• 1.0 mp = 15 bc in rush build cost.
• When a colonizer (resp. transport) is completed, the full population is drawn from one of the sponsor planets, by an algorithm I don't know.  (It could be as trivial as: closest planet sends all.)

We weave all of these to teleport civvies.  This is sweet in two ways: it gets people out of your backfield, and you don't need any manufacturing prowess to do it.  Its manuf cost to you is zero.

1. Let C be your bankworld or techworld, with no manufacturing tiles, deep in your interior, nearly full of population.  It has no shipyard.  Even if it did, its build rate would be lousy.
2. Let F be a frontier forgeworld, with nice build rate, but low population.  In the same system is G, an empty planet.
3. F builds a shipyard F' (or borrows one nearby).  At F', it constructs a colonizer with no engines and no range (because why bother).
4. F nigh-completes the colonizer, i.e. leaving less than 15 bc of work remaining.  (You can see this when you hover over the Build Now coinstack icon.)  This means 1.0 mp of shipyard build will complete the colonizer at F'.  Compute the mps you need from all other sponsors so that you "come up just short" by < 1.0 mp.  (It would be a disaster to actually complete the colonizer by accident.  Reload game.)
5. In the turn of completion, Manage F', remove all sponsors, and add C as the lone sponsor.  C can be 40 hexes away (it doesn't matter).  Set C's Govern slider to 100% shipyard (right extreme).  C's wheel can be set to 0% manuf.  (The one time I did this, it was with a techworld at 83% rp, 17% bc, 0% manuf, at a distance of 17 hexes.)
6. For shipyard F', in the Manage / Add Sponsor menu, C will appear in the list with its distance in red, and a note: "1.0 mp".  I think this is supposed to be the upper bound, but it got implemented as the lower bound instead(!!).
7. Hover over shipyard F'.  Its lone sponsor C will display as contributing "0.0" (which is, indeed, true).
8. Click on shipyard F' to select it.  In the lower-left Shipyard bar, it will say "1.0 mp - 1 turn".  This is a phantom 1.0 mp from a remote shipyard.  (These phantom 1.0s do actually add to your build, exactly as if you had delivered a real 1.0 mp.  They reduce the "buy" cost by 15 bc each.  You can dogpile many remote worlds onto 1 shipyard, and they will contribute exactly 1.0 * N mps ... even if they don't send any.)

On the next "Turn", the phantom 1.0 mp becomes real, and completes the colonizer at shipyard F'.  Since C is sole sponsor, it sends the 2.5 bp.

Ergo, you teleport 2.5 bp a distance of 40 hexes ... for a cost (to you) of 0% mp and 0.0 mp.  You don't even have to Govern the wheel.

Use new colonizer to colonize G.  Faster and easier than, say, having C actually build the ship on its own, and then driving it there.

6.  Missionary Center does not give +1 Benevolent point per turn

Apparently not implemented.

7.  "Destroying" a not-yet-built Missionary Center prevents rebuilding it

This could be endemic to all one-per-planet items.  If you enqueue a Missionary Center, but remove it from the queue before any construction is started on it ... it still does not reappear in your planet's build queue.

Canceling an intent should not count the same as destroying a tile that actually exists.