Thanks for the link.
I have now installed a secondary 1TB HDD as SDB, mounted it via fstab to /media and created a symlink to the /home/userXXX/torrents folder. It's working and the permissions are set, Torrents are running just fine.
However the disk space reported in the widget and in rTorrent is wrong. Can you help?
Are there a better way of doing this, rather than symlinking the folder? I think this might be what is causing the issues.
EDIT: I've now mounted /home on the 1TB drive in stead, seemed like a better solution. rTorrent is now reporting the correct amount of disk space, but the widget is still using the disk space from "/".
EDIT2: fix-disk_widget_home solved the problem! Should I be running into more problems after this?