I too am having an issue with this plugin. I am using Twenty-Ten theme with a Child Theme directory that only contains a style.css sheet. I cannot figure out which file to place the <?php the_block('name'); ?>
I am receiving 4 lines of this error: Warning: fopen(/homepages/15/d297112724/htdocs/wp-content/themes/twentyten-child/page.php) [function.fopen]: failed to open stream: No such file or directory in /homepages/15/d297112724/htdocs/wp-content/plugins/multiple-content-blocks/multiple_content.php on line 64
Is this an outdated plugin that is not functioning or supported any longer? I haven't seen any recent replies to people's questions about it.
My main intent is to create a new full page width content block that is the width of the existing content block along with the width of the sidebar. Maybe I am attempting this the wrong way?