with the latest iOS version of MM2 there is a little bug during the download of the course's resources (file).
In order to replicate the problem:
1) add several PDF to a course topic
2) gain access to that topic by means MM2.
3) click on the icon to download the file.
4) in the meantime (whilst it is downloading the file) click on the resource name, so click on "open the file".
5) The App will show the modal "Download in progress" forever.
Also, times ago arose the "problem" to have the name of the file instead of the "file pool ID". Do you have in plan to perform this change?
Best Regards, Claudio