i always use indydebi's butter-cream recipe...and i always use whole milk. however, i totally forgot to buy some and only have 1%...will it be okay to use that?
Should be fine. I've also used non dairy creamer (the powder stuff) mixed with hot water. That's Sharon's method.
I've heard of people using straight water to thin their frosting. I prefer to stick with something that will add creaminess. Besides, we all know water and fat don't mix, so how does adding water help? But people do.