Scenario A:
Another tech queued after the current one.
After tech is finished, there is some % already done on the next one.

Scenario B:
No tech queued after current one.
Selecting next tech will always show 0% done, regardless of how much overflow was from the last research.

Scenario C:
Another tech queued after the current one.
After tech is finished, there is some % already done on the next one.
If I switch to different tech, 0% is done, but switching back to queued one will also show 0%. Overflow is lost?!?


Does this system work correctly?

It seems overflow only functions in next tech is queued. And you must not cancel that tech (at least for one turn), otherwise overflow is lost.

What I´ve found is that the tech in queue gets the overflow, regardless if you de-select it or not. In case no tech is in queue, the overflow is applied to the first tech you select.



I´ve never seen a "research progression" description for each tech, I only assume that from the number of turns it takes.

I don't think overflow is lost if you change tech selection. What I can say is different techs cost different research points. Say an overflow would show as 10% in the bar of a tech that costs a total of 100 points for example. But it would show as almost 0% if a tech costing 1000 points is selected for example due to different proportion. At least that's my understanding.

Well, in all my cases that was not the case. If no tech is selected, whatever you select will start with 0% progress, but if you queued something then progress will always be over 0% for next tech.



Additional thing that I discovered is that if you abandon researching the tech, later when you want to research it again its progress will be nullified.



This is especially bad if you started end game research, but want to research something that you need quickly. All progress will be lost.