Hi Soozsb,
I find the dd's a lot easier than the up days. I think it's because you feel so in control on dds and know you only have to stick with it for a day, then tomorrow you can eat. Up days are a bit harder as it's easy to go overboard, I really had to keep track of mine, but must say they are getting a lot easier now and have leveled out lol.
I have a diary in the diary section
http://www.minimins.com/juddd-diaries/114077-stirkys-juddd-journey.html so you can see what I eat on both dds and uds. On dds I leave it as long as possible to eat. Tends to be around 2pm, maybe later. I like to have low cal soups, salad with ham/chicken/turkey slices, crackers with exrta low cheese spread and usually some cucumber, and low cal snacks/popcorn etc. There is loads you can eat for 500 cals if you look around. I like to break mine into 5 x 100cals that always works well for me, most of my stuff is under 100cals anyway so save on cals there.
I think we all do get those weeks where we stick to it and lose nothing, it can be annoying but we just have to keep plodding on. I'm sure you can lose a good bit of weight if you stick to the plan and remember to drink plenty of water, it really does help esp on dds.
Good luck hun and keep us posted!!