I am having download and upload issues with documents on Coursepress Pro

Hi
I have set up a course via Coursepress Pro and it currently has three modules with various unit sizes. The issues we've been having so far are that I have uploaded handouts and my powerpoint presentation for the students to download, and when they have downloaded the document, they have turned out blank. I thought this was an issue with the version of word/powerpoint the students have been using but all of them have had the same issue. In addition, one of the other elements of the course is the students can upload a part of their assignment using the upload system, however I have just tried to download their submissions and they have all been blank. Some of them are .doc files and others are .docx. Please can you advise what to do as this is currently stopping me creating more modules.