Align YARPP under single post

Hi, I would like to align complete ‘box’ with thumbnails and titles to center like it is shown on the picture.

Other thing is that red line. I would like to add that line above that ‘box’ because in case my article is too short I get mess with thumbnails and in case of that line that thumbnails would be arranged and aligned with that line, like adsense box is on the picture you see.

http://s30.postimg.org/8jzw0203l/Untitled.jpg

Thanks

https://ww.wp.xz.cn/plugins/yet-another-related-posts-plugin/