Fixing Qtranslate slug problems
There are basically two options when creating a multi-language website based on WordPress. One involves duplicating posts and pages by creating one different post for each language, wich is the approach followed by some plugins like WPML, Polylang or xili-language. Another approach is to introduce all the translations into the same post, separated by meta-tags within the content itself.
Each translation is displayed in different tabs within the HTML editor of a single post. This is the case of Qtranslate, which happens to be the simplest solution from my point of view, as it is not necessary to modify the WordPress database in order to create relationships between a post or page and their translations, as well as among other WordPress objects like categories, tags, widgets, menus, etc. Therefore Qtranslate is my favorite choice when it comes to creating a multilingual website based on WordPress.