First, game runs much much smoother/faster in latest branch.
Game Setup:
Normal everything.
Bugs happen at any point in the game, though I am 300 years in now and everything is still smooth/stable (other than random ones popping up).
The Minor/Medium in parenthesis is how much of an issue I determine it to be, it could be trivial to others.
System Generation and Display Tab (Medium+):
After renaming a system (e. g. Groombridge 34-A to Groombridge, etc), you MUST exit the window or there will be no auto-update.
Normally, swapping from 1 system to another will auto-populate the newly selected system.
After renaming, there is no auto-population.
Economics Tab (Medium):
After renaming a system (example above), the moons/planets that were already colonies retain the previous name in economics tab.
The names are updated on the System Generation and Display Tab, yet also retain the name under the colony info (i. e. {Race} Gloombridge 34-A Moon 2, even though the title has changed to Groombridge Moon 2).
Event Log (Minor):
On death / retirement, current assignment should be listed as previous assignment.
On death, current assignment will properly show what they were doing/researching.
On retirement, current assignment will NOT show what they were doing/researching.
(Even more minor, no auto re-assignment for civilian administrators is meh).
Ship Construction (Minor):
When specifying a ship as a tanker/harvest, there is no minimum fuel level set.
While you can set the minimum fuel via another tab, choosing it as a tanker should auto-reserve 10% of the max fuel capacity.
Otherwise, starting as a "tanker" yields 0 fuel on creation and when emptying (via manual or set orders) will empty all, without reserving the 10% needed to complete the return trip.
Research Screen (Very Minor):
If in a rush or lazy (i. e. dragging the mouse to select multiple units instead of choosing ones individually), you can select a non-research (I. E. the blank box).
Error pops up with "Function #585: Object reference not set to an instance of an object.
Colony Creation (Minor??): (edit: While this is known by Emperer God Overlord Steve, I've yet to attempt to break the game with it)
You can create multiple colonies of the same planet/moon by hitting "create colony" multiple times.
I have not tested to see what comes of this.
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(1. 6. 3 bug that I did not get around to mentioning)
A civilian mining company created their own colony on Mercury ( IIRC they had set up mining industry and I terraformed it to be habitable).
They had started a CMC on Mercury, I created it as a colony so I could land terra equipment.
After terraforming was complete, both the CMC population and my Mercury colony population started going up, leading to instability.