Modify the Metro theme for phpbb

I think this is a very small job for someone to fix, but I've tried many different things and I can't get it to work... Here is what I need you to do... I purchased a phpBB theme, to integrate with my Wordpress site using the WP-United plugin. You can take a look at the theme I purchased here: [login to view URL] You can take a look at the WP-United plugin here: [login to view URL] I set up the plugin and the phpBB forum integrated into my website perfectly and it was working 100% fine with the default prosilver theme. I then installed the Metro phpBB forum theme I purchased from Themeforest and applied the necessary changes to the theme files to get it to work, but the layout is broken on my website, when my browser is full screen. You can take a look at it here: [login to view URL] The crazy thing, is that the forum's responsiveness works just fine. You can see for yourself by resizing the browser window. But when the browser is full screen, the layout of the phpBB forum is too big and doesn't align properly. I spoke to the developer of the Metro phpBB forum theme and they said that it should be easy to integrate with WP-United, because the theme is built on the default prosilver phpBB forum theme. All I need to do to get it working is to decrease the "main forum block width", but I'm not sure what they mean and I've tried editing various widths and the phpBB forum never changes on my website! Then I would like to remove header with "metro" "faq" "membres" but I don't know how to do it If you could help me I'd really appreciate it, I need this job completed for Saturday, so I want to award the project soon and make payment as soon as the job is complete! Thanks a lot!