preface: am a non-english user which means descriptions may vary from original english version. sorry for language issues in advance.
depiction issues / building icons in "available improvements" list
pictures of some improvements often become black especially when razing buildings (and) switching colonies by arrow keys. example is in the picture, mouse was on such an improvement just right of the text. In fact you can "look" at 4 such buildings here. you can even drag/drop them to build them. sometimes the icon then does also not appear until building is completed.

adding usable planet areas
over the course of the game you might add 5 areas via upgrades on any planet and just a few via event rewards or anomaly rewards. despite the fact that the random ones should be placed next to existing terretory (not the case) and the fact, that some planets have too less upgrade spots (which is also accaptable) and the fact, that later upgrades cannot use all spots while the 1st upgrade can do so, which is annoying there is another issue
in late game (circumstances not completely clear) some spots disappear again, and this is extremely annoying. am not sure if it is (may be) connected to rosalind story path or to mastery in a 2nd culture path or whatsoever. might be its even connected to some end-game tec
one-per-planet/empire-improvements
well this one is nearly funny. let me post a picture, that explains most.

At the moment (current version on steam / 2023/nov/24) you could collect lots of those buildings by conquering just one other civilization. raze the building on the newly conquered planet and build it elsewhere. the civ will create another likely.
Yet i have no idea how the cpu manages to produce those setups (found 4 mainframes and 3 heritage centers on one planet each)
As described you can transfer one such building from one planet. if you raze the 2nd, you cannot transfer the 2nd. it even seems if transfer after that is completely broken.
thats all for now, even though unfortunally there are other bugs (outside colony screen)
Spirit