On my computer I find the PDF-file under C: > ProgramFiles(x86) > Magix > Movie_Edit_Pro_MX_Plus. It is a document of about 400 pages in many languages.
Also, if you are only trying to blur a part of the image, i.e. not the whole of each frame, I recommend you view this video tutorial http://vimeo.com/9515252 created by a long-time user of MEP.
Effects masks were introduced in version 17 and carried over to MS. These would be perfect for what you want.
They are used to apply effects to part of your video clip. In your case your effect woulfd be the "sharpness" effect under video effects.. n the little down arrow in the effects windo, choose "Load Effect mass". Then choose a mask. and adjust the sharpen window.
There is a little eye next to the Blur effect inthe keyframe area. I think you need to hit that sto activate the effect mask.
You can be creatuve and create your own masks too. You can also keyframe the mask if needed.