I'm using the last version of WordPress and qTranslate Slug plugin too. I use on my website 3 languages. If I want to add into english version page URL to other english version page, it redirect me to page with translated slug, but without language selector and the result is a 404 page. (English is not the main language.)
In "http://www.website.com/en/project/" page editor I want to add URL to page "http://www.website.com/en/something/". But when I click at this link on the published page, it redirects me to "http://www.website.com/something/" without the /en/ selector. The link redirects good only if I use "http://www.website.com/?p=ID&?lang=en". And when I write directly in the browser "http://www.website.com/en/something/", it works fine too.
I search some solution last 3 days and I tried all what I found (other permalink structure, all possible qTranslate options, my .htaccess is writable, etc.), but nothing works.
Thank you so much for this great plugin and I hope, we'll find some solution.