I am making a cake for a birthday and the client wants beer bottles on it. I am going to attempt to make the sugar ones (but if that fails, I might just make them out of chocolate). Can anyone tell me if I need to add anything to the sugar / isomalt to get the brown beer bottle color? Any advice would be appreciated!

a few drops of brown and yellow...sometimes you need to add a drop of red- depending on the brown you use. Just start with the brown and see what it looks like.