downloads (attribute type)

Hi
Is there any manual about how to use download attribute type?

In the help it says "Download files from the product, e.g. manuals, data sheets etc." so I assumed that this is exactly what I need to provide some file downloads for product which is publicly available.

When I created this attribute, specified files on backend - everything was as expected. But in frontend it looks very strange:
string(34) "a:1:{i:0;s:16:"?A5H���}'s�";} (yes, not utf symbols, but file name is in English)

I just need to add access to the brochures for the product., and make sure that user can download file without any problems.