You're supposed to move them with the mouse... Now if you're saying to me that you can't move the dots in the other square... I think you have might have found a bug that i wasn't aware of... :/
As for the "sometimes tea gets gone randomly", i forgot to remove the cheat keys form the game, so maybe you press it while trying to figuring out the controls... try to make a random tea with 4 ingredients and let the dots touch each others, if the tea still manages to be done then you have one of them activated... (Restarting the game should reset the cheats)