Following this particular article, I am sure that the new files does not gets copied, but the already installed one will be updated only.
To copy the new files, you have to do the work as done behind the Modify option thru which you can install the new files in a component.
Therefore, first call the function ComponentSetData to select the components that have new files. Then call the ComponentTransferData explicitly.
I hope that this will work...!!
"In theory, there is no difference between theory and practice. But in practice, there is." - Yogi Berra