(Its not bugs, its issues)
1. When you try to cancel a building upgrade through the City Management Screen, a confirmation page will appear telling what will happen if you cancel, and the two options given are: Ok and Cancel. Very misleading, since Cancel doesn't cancel the building...
2. When you try to cancel a building upgrade through its info page, no confirmation page will appear, canceling without prior advice (just lost 6 hours of work testing this lol)