Hi
I would suggest that you get a copy of ImagesPlus, I note that you have a 400D, ImagesPlus can be used to focus and automate your images, convert, stack align, combine your Darks, Flats, Lights and Bias as well. It also has a number of Image Processing options as well.
For the 400D a complete package. Not free but probably the best of them.
http://www.mlunsold.com/
DSLRFocus does not yet support the 400D.
Cheers
JohnG