Same problem with the tablet not being used and not getting hot, I had this problem last year it turned out to be the heater element had gone, if the dishwasher doesn't get hot the tablet will not be released, guess what people it's back again this time i will be fixing it..
http://www.buyspares.co.uk/dishwasher/mfi60/heater-element/product.pl?pid=1112808&shop=matsui&path=125697&model_ref=49049
muffin muncher, October 2010