The theme at http://p2demo.wordpress.com/ and available for download at http://wordpress.org/extend/themes/p2 are different.
In download version it uses author nicename for author pages. sitename.com/author/author name
In wordpress demo its using author login name
sitename.com/author/authorlogin
So even if nicename is having spaces demo theme works well but download version doesn't show any post.
In download version there is bug in mention feature @authorname
while in demo version its working fine.
Please update the download file as soon as possible.
