Ok, I had tested in Version 2.00+ Build 130219 and this problem still exists there - not only with the default template and my modification of it but with the bluengrey template also (so I assumed, it is probably a general template problem).
I then did some searching in the limesurvey files (of my LS 1.92 installation) for the term "completed.pstl" and found this piece of code in the file group.php:
echo templatereplace(file_get_contents("$thistpl/completed.pstpl"));
echo "\n<br />\n";
Simply deleting the line
(seems to have) solved my problem without any adverse affects and, for now, I'm a happy camper
So two last questions:
1.) Does anyone think that my solution ist not a good idea? (And if so, please be specific)
2.) Do I still 'have to' open a ticket on the bugtracker?
Thanks
Thomas