Tracy, Medrol 8 mg is equivalent to 10 mg Prednisone, and I couldn't effectively lose weight until I got down to 7.5 mg...for some reason it just seemed to be my magic number. My doctor told me I couldn't lose weight on steroids, too, and almost accused me of stopping the Prednisone when I did lose weight.
I did find that with each wean of steroid, I was slightly better able to control the appetite cravings and surges, for example the final 10 pounds I put on while taking my maximum dose came off when I was dropped to half that...that was a relief, because I found it was that 10 that seemed to give me the Cushingoid appearance, under that I just looked fat.
Most annoying to me is the distribution of excess weight; in the past I've had overall but proportional weight gain with my back seeming to take most of it; with steroids my face got rounder and I have a "belly" but my arms, legs, hips and back are not that much bigger than they were. Through 50 pounds up, 30 pounds down, and everything in between, the only things that haven't fit have been things fitted through the torso (tops with fitted shoulders and sleeves, but lose bodies still fit, as do "comfy" pants with elastic waists) and my glasses!
The steroid cravings were ruthless, it wasn't just a matter of "I need such and such to eat" it was "what can I eat next" while I was still swallowing, and the NEVER feeling full, no matter how much I ate. It was getting up in the middle of the night starving to make a pot (not one bowl...a pot) of oatmeal and eating the whole thing with sugar (and I had to go out an buy the sugar the first time because I didn't keep any in the house then). It meant buying candy! I never had much of a sweet tooth before steroids, and thank goodness it's back to my normal of slight nausea with white sugar or anything containing it.
Since my 3-5 days a week at the gym aren't possible anymore, I have to rely on portion control and healthy food choices to lose anything now, but it's slowly working. Luckily I've always been a bit of a naturalist when it comes to food...I prefer locally grown for the most part, non-processed, minimally packaged, "real" food. Of course I can't get local grains like rice or quinoa, or my very favorite steel cut Irish oats, but I'm not a fanatic about it! I try to avoid anything with the word instant on the package, and (except for dried pastas, beans, grains or fruit) any thing that has a longer shelf life than I do. It isn't convenient food, but I have a lot of time on my hands since I retired. Even when I was working, I cooked on my days off and had my own packaged meals for busier days.
I have to actually measure everything, if I don't I find I'm a very generous guesser! I keep a glass of water or cup of tea (black, green, white or herbal) at hand constantly, and snack on almonds or half a cup of dry cheerios when I need the "chew factor". Cinnamon is my secret weapon, I love it and add it to just about anything that I think needs a bit of sweetness. It has also been shown to help control blood sugar, although that hasn't been an issue for me, even on steroid.
Like any other aspect of living with SjS (and steroids) weight loss is individual and trial and error...you will find what works well for you. Try not to worry about "giving in" to the cravings...once in a while! Your graham cracker snack sounds great, and maybe you could (once in a while) just skip the low fat margarine, every little bit helps, and most of the flavour in that snack would be in the cracker itself and the strawberry preserve.
