Full description about file limitations
Right now there is no way to see in the dropzone what exactly mimes and maxFileSize are allowed. It would be very helpful to see that before user selects some files. The message could be like: "Allowed file formats: jpg, png. Max file size: 2Mb"
I would also like this feature. My workaround was to add it on the "open" event.
DocUppload.on('open', function(){
//include docTitle and helptext
$(DocUppload.container).find(".uppload-service--local").prepend("<input type='text' placeholder='Enter Document Title' class='input' id='docTitle'>");
//add helptext
$(DocUppload.container).find(".drop-area").append('<p>Allowed filetypes: pdf, doc, docx, jpeg, png<br>Maximum File Size: 5MB</p>');
});
Which produces this:

Makes sense, great idea!