What does this message mean?
1 document was uploaded but not visible because it does not match the current filter.
I just received this message myself. I did have filters enabled (a single property selected) when I did the upload. At the time of upload the new document does not have a property, nor a category associated with it, consequently, once it is uploaded the filter will not let you see the new document. Simply clear all filters and the newest document uploaded will be shown. You can then attach it to a property and assign a category.