I am working on a similar application for DAAD, only it's a scholarship for a PhD.
I am also not sure, what exactly do they want - the description of the research project plus SOP and the motivation should be in the total length of 5-10 pages.
now, im uncertain about how should the research proposal be - should it be a scientific text, with all the techn. terms and citations, or a more friendly explanation to people outside the field (im guessing more of the latter, since the reviewers are not from one field).
evenso, i have discussed my research project in details with my supervisor yet, as i will start only in october. that is why i'm even more confused on what do they expect, since clearly at this point i am not able to give a details plan of the research, beside the general field.
regarding your application for a master - is it in Germany? if so, it isn't research oriented, rather more a taught master. that means your main focus in studies will be doing courses and taking exams, so i can't see the point in spilling out your research ambitions at this stage.
do they specify how many pages should it be? any more details?
If it asks about a study program, which is a taught master, than im guessing you should basically explain what is your interest in this field, and how it relates to your previous studies.
good luck!