EDIT: reloading the savegame after turning off all research seems to work

thats a weird one thats been around for a while, normally when the buildings are built it runs the checks for research steps, and then they happen again every 2500 ticks just in case they didn't when being built because of some mod patch, but in rare cases it never processes at all, i have never seen it happen in testing, so maybe just mod compatibility things

reloading the save file after spamming some buttons worked.
might be the fact that i tried building it in a separate colony than my main.
or that i deactivated the research, then built it, then activated the research again.

or maybe try doign the trigger the other way around: when the table gets built, it sends out a ping to the research script or so, in addition to your way of checking right now. that way, at least if i rebuild it, it should trigger?

but yeah. had it happen once in a multiplayer game, and once in singleplayer with an entirely different modset.

well its got a timed check that always runs anyway so as long as the project is active if you wait a minute it should check

okay so i figured out that when you have multiple colonies / maps, the research gets kinda buggy, as in you need to have every prerequisite on the same map, then restart the research on that map, and then maybe reload the save for it to work.
seems to work alright if you never use multiple maps, i.e. never built any additional colonies or camped somewhere with caravans.

odd, the research is in a world component and loops all maps to run the step completion checks, maybe a mod messing with it