Asc/Desc not working

Hi, I Install your plugin – and I must say everything is great except one thing:

On widget, plugin always put the first upload pdf file on top, and the latest file and all others after latest…

example:

Listić župe 222 – 06. siječnja 2013.
Listić župe 232 – 17. ožujka 2013.
Listić župe 231 – 10. ožujka 2013.
Listić župe 230 – 03. ožujka 2013.
Listić župe 229 – 24. veljače 2013.

I change the date of publish, everything seems ok, but I can’t fix these problem,

please help,

http://ww.wp.xz.cn/extend/plugins/wp-publication-archive/