I just had a problem with my Gala toilet. The water wouldn't stop coming into the toilet after it was flushed even after attempting to press the buttons several times it wouldn't stop. As the person above said you have to remove the two flushing buttons and a large philips headed screw is underneath them this is what attaches the flushing buttons to the main unit inside the systern. The buttons are removed one by one and the casing doesn't have to be touched as now you can unscrew the large screw. The problem with me was that the unit inside had moved and was not sitting in the correct position. Once I turned it slightly it fell back into place and then I just had to reasemble the buttons etc. I hope this information is of use to someone. Also for some reason tightening the screw fully caused the water to start to flow into the toilet so I have had to loosen the screw until the water stops once filled. I don't really think that this is correct but it seems to work for me.
Christopherson, December 2013