Yet another interesting but appeared after loading last nights save game...
Related to this save game: https://forums.elementalgame.com/380031
Every single building, that was already build when the save game loaded, shows to be in a perpetual state of under construction. Only the buildings I built after the load show as having been completed.
Note:
It also seems like my improved housing tech was not applied to the housing of towns after the save game load. I had to build more houses to grow towns that where growing just fine BEFORE I loaded the save. I will do some testing to find out if my suspicions are correct.