Plugin slows down my website

Hi,

This is the best translation plugin and language selector there is. The only issue is that is slows down my website, pages take 5-8 seconds to load if plugin is activated and logged in, otherwise (if deactivated) 1-2 seconds. Also, the toolbar disappears if plugin is activated and logged in.

Is there something i can do about these issues?

Thank you!

http://ww.wp.xz.cn/plugins/wp-native-dashboard/