As a relative newbie to owning a dishwasher, is it normal to get this kind of gunk and build up on the inside? This is when you pull out the drawers, though around the seal of the door is a bit dirty too after a wash. I am trying to get into it with a cloth but can't get it all out these drawer runners. It's a fairly new slimline Bosch and we do scrape plates though there is obviously bits of porridge residue on bowls, baked on bits on ceramic oven dishes etc. and I'm sure it should be designed to handle that without needing to take the whole thing apart! Oh, and this is not the first time I'm cleaning it so it would be even more caked if I'd left it! What does everyone else do?