Unfortunately the controls are a complete mess.
It takes several tries to hit the hitbox of anything (even buildings). This makes it nearly impossible to repair/fix anything. Maybe there exists some kind of offset between the actual mouse click and the area where the game _thinks_ where the click has been.
I tried it in the itch-app and directly in the browser - the browser seems to have worked a bit better (at least in fullscreen mode) but overall still more or less unplayable.
Maybe you can add a small dot or circle on the position where you _think_ the player clicked so that there is a possibility to at least manually "adjust" the mouse offset.