It looks as though there are a few issues with linking to the other files on your pages. When I check the source I can see that they are all set to file system paths. It looks like when you made these edits you did not have the site properly defined in DW. You must first have you site setup in DW including the testing server info so that any changes you make will be incorporated into the site correctly.
The Warning: require_once(../CSSMenuWriter/cssmw_home/menu.php) error is letting you know that you have the menu writer include referenced on the page with a ../ in front of it. You need to make sure that it does not have this ../ in front of the path on your page.
If you have a hard time getting it all set back up you should revert to the original downloaded files and start fresh with those. Make sure that you define your site in DW before you attempt to make any changes or you can have other issues as well. Here is a link to a how to on getting your dw site defined: