Layout of the password page

Hello,

I download the plug in for a special costomer project. It works great. But I have a big problem. The page where my costomer arrives look horrible. The layout is not center with the rest of the website. It is not appearing on the page template I would like to. Is there a place where I could change this preference. I would like the layout of a page named no-side-menu.php Is it possiblit to do this by changing a line in the plug in template ? Thank you. Hope this is clear. English is not my first langage…