The input type="file" issues:
It is impossible for now to have a beautiful cross-browser field only with CSS styles. The only way to control it is to add .js files.
This blog show the main issues: http://viget.com/inspire/custom-file-inputs-with-a-bit-of-jquery
We can try to use something like http://www.kavoir.com/2009/02/styling-file-upload-select-input-control-input-typefile.html ?
I'm not sure about the licence.
Also, it is possible with scripts to display, in the field, once the file is picked, only the name of the file, and not a 6 kilometers path. If we do that, it can avoid problems like