Hi -

What you use as a substitute generally depends upon the recipe/purpose
you're using it for.

If the cottage cheese is being baked as in a cake, then you can probably
treat it as a liquid, but use less of your liquid substitute than you
would of the cottage cheese since the cheese isn't 100% liquid.  If it's
being used for texture, as lasagna, then some sort of tofu might work well.

How is dry milk used in peanut butter balls?  If it's being mixed into
the recipe, you might be able to just omit it.  If it's for rolling the
balls in, consider powdered sugar or cocoa powder.

In some recipes, like quiche :-), substitutions just won't work.  They would
change the recipe so much that you wind up with something completely
different.

My web page has a *few* substitutions on it, although not the specific ones
you mentioned. (Maybe I'll add them ...)

I hope this helps,
--Beth Kevles
  [log in to unmask]
  http://web.mit.edu/kevles/www/nomilk.html -- a page for the milk-allergic
  Disclaimer:  Nothing in this message should be construed as medical
  advice.  Please consult with your own medical practicioner.