I'm working as a one-man user interface team for Kanbanery and I'm currently working on improving our user interface and user experience for task attachments. Currently we support two types of task attachments - regular attachments (just shown as a list) and attachments that we can preview (images etc.) that generate a thumbnail.
My task is to make it obvious how to preview and how to download attachment without making it too busy (our UI is pretty busy as it is).
Currently clicking on thumbnail expands the image to a modal window and clicking the title (or the "arrow down" icon) downloads it. I don't think that's obvious enough. Also, I don't like the fact that big pictures take so much space.
Any ideas on how to improve it?