I understand the UI does have some issues at 4k resolution but I’ve set the scale higher up and when trying to place buildings, roads, basically anything peaceable. The UI will cover the cursor so you can actually see the tile the object will be placed on.
Also side note, most building menus will snap to the right side of screen/half off screen when selected. EG the trader menu will be snapped to the far right, requiring the window to be moved in order to see the full options