Hi!
I have the Polylang ‘autosave’ problem, too. New to WP, so can’t tell about versions before WP4.1. Clean WP 4.1 install with 3 noticeable changes from ‘default’ install:
(1) WP is installed on a subdomain -> testsite.mainsite.com; there is a different WP instance running on the main site (different WP directory)
(2) I have the SEO plugin “WordPress SEO by Yoast” installed.
(3) In polylang settings, I have changed the Sync-Settings to include:
page template, published date, page order, comment status, post format, featured image, ping status and page parent.
All the rest should be pretty much standard.
When editing pages or posts, flipping back and forth between translations (after proper save/publish) creates an autosave-version despite the proper manual save.
In the pages list/overview for each page there are 2 page entries one with English ‘checked’ and German ‘pencil’ (for the english page) – the German page respectively shows English ‘pencil’ and German ‘checked’. (I guess that is how it’s designed to be, but not sure since I couldn’t find a screenshot in the online help/blog).
Help much appreciated!