Hey, HIO. I'm sorry you have to do this. It's so hard, especially in the beginning.
If I were you, I'd do a lot with potatoes at the beginning. You might want to invest in a fryer, if you don't have one already. We made our own french fries instead of getting pizza or burgers for a while there. You can also mash them, make oven baked chips, and bake them, and fry up slices of them with a lot of sea salt. They're pretty useful.
You know, I was thinking that some raw food and vegetarian cookbooks have great allergen-free ideas. I have a cookbook called 'yoga kitchen' that's full of great ideas--like southwestern quinoa pilaf, and millet croquettes (I think), and a lot of veggie dishes with a lot of spice and flavor, but limited allergens. It's pretty full of Hindu philosophy, but the recipes are good.
If you can come up with a substitue for eggs, the grain-free gourmet has lots of recipes using almond flour. But they also use yogurt, butter (can she eat ghee?), and eggs, so I don't know if that one would be a good one for you.
They did have an idea for taco shells: You can bake rounds of provolone cheese on low heat in the oven until they are browned and a little crispy around the edges, but not completely falling apart. Set up a broom handle between two chairs, and cover the handle with paper towels to create a clean surface. Then, when the cheese is right, drape it over the handle until it cools. It comes out looking just like taco shells. There's a bit of an art involved with this, so they say, but it looks promising, if you can't do corn.
My kids have learned to love rice and curry dishes. You can make curry sauces that flavor up chicken, that don't have allergens in them.
For baking, that would be really hard. I have a recipe for coconut macaroons, if you want them. I also have a recipe for non-dairy chocolate pudding made with young coconut. It's posted on WTM somewhere. They don't have your no-no's. The no-egg problem is pretty hard to work around, bless your heart. I'm thinking that if you can come up with an egg substitute, though, the world will look a lot better.
Also, in most of my cookbooks, they say ghee is cassein-free, it might be worth trying. Also, spectrum makes a veggie shortening that could sub for butter.
I was thinking that you could make (or buy) sorbets this summer instead of ice cream for her. You could also do frozen fruit smoothies, or berries with syrup, or baked apples with (gasp) cool whip (nondairy).
If you get a dehydrator, you can make flatbread crackers for her to use as dippers. A dehydrator helped us a lot when we didn't have a lot of food options.
Well, I hope this helps. I feel for you, and hope you get it worked out.