Hi Dienia, I cannot help you with the dumplings. The coffee cake sounds like something my mother made - she never used a recipe, just put ingredients in the bowl until it looked right - or perhaps she had memorized it. it's this one, I think,
Libbie's Czech Apple Coffeecake
It's more like a batter bread - the dough will be quite soft. You don't use a lot of yeast in relation to the amount of flour, so it will take about 2 hrs to rise. I think you will need more apples - you need to put the apples on quite close to one another to cover the top, because they will separate as the dough rises between them. I made something like this a few years ago while visiting my dad and that was his complaint - not enough apples on top.
In terms of the directions, I'd change step 2:
put in mixing bowl with the 2 cups water, 1/2 c sugar, salt, egg, shortening a little lemon flavoring 6 cups flour sifted. and beat until a soft dough forms.
Step 7 - the melted shortening seems to be used all in the dough - so you need more here. I myself would use butter on top (and in the dough itself), it would taste better. Only butter on top. I think you would need about 1/2 cup of melted butter - 1/4 cup on each of the pans.
Step 8 - I would add that you will need enough sliced apples to cover the top of the dough closely.
I would bake at 350 deg - it will probably need somewhere around 45 minutes at a guess. 425 seems too high.