We have released an upgrade to the plugin/skin packages that includes some fixes and improvements, especially applicable to those, who use Roundcube 1.4.x. We fixed the logout page errors; problems with some old config options not working properly on RC 1.4; database query quotation problems on Postgres; and a few other minor issues. The new version of the software is available for download in the customer area of our website.
Alternatively, if you want to always be running the latest version hassel free, try our cloud based RoundcubePlus Atlas here: https://roundcubeplus.com/atlas-webmail-in-the-cloud