When I try to clone a redstone contraption I made myself /clone command actually does its job but things then get totally broken: I cannot open menu, pick blocks and dounds completely disappear.

Last but not least, by saving and quitting the game is not able to save and stays in saving screen for a non definite amount of time since I closed it after 2 minutes waiting.

When you get back to the world it restarts at the exact position you was before using the clone command.