Hello,
I couldn’t manage to force redirect to https, based on the instructions here and in the .htaccess-file.
After some searching I came across this post: http://stackoverflow.com/questions/4083221/how-to-redirect-all-http-requests-to-https
which solved my problem. (And, according to the comment on Stackoverflow, is also the “new, correct” way of doing it.)
In .htaccess I replaced
RewriteCond %{SERVER_PORT} 80 RewriteRule ^(.*)$ https://%{HTTP_HOST}/$1 [R,L]
with
RewriteCond %{HTTPS} !on RewriteRule (.*) https://%{HTTP_HOST}%{REQUEST_URI}