Shouldn't the top level table be allowed to automatically calculate the width instead of forcing it to 100%? Things like height and width normally should be dealt with in styles, not forced in the HTML.
This plugin broke layout because it forced its width rather than let the browser handle it.
Line 402 should be:
<table cellpadding="0" cellspacing="0" border="0" class="' . esc_attr($class) . '">' . $caption.'