Tracking of downloads isn't working right for non-www domains (i.e. blog.example.com). Technically, it actually works, but the tracked url looks bad ("/downloadsblog./path/to/file"). This is because of line 475 of googleanalytics.php:
$file = str_replace('www.',"",$file);
I fixed it locally by changing "www." to "blog.", but obviously there's a general way to do this. Just thought I'd report it.