-the navigation below... (see image) is better when you assign/sort the button(s)
my old 4.0 version (see image) is easy
The problem with your layout is that its confusing because "save date" only used with copy/move buttons, in your layout it looks like it used with "change owner" button. (btw, in english translation it looks different
)
Anyway, first of all thank you very much for testing this and reporting it back, secondly, I've updated to v4.0.3 where I changed the buttons layout a bit, more like you did in v4.0, hope its less confusing now.
I've removed some of the deutsch language translations (replaced them with english), they are separated from the rest so its easy to spot
$lang['copy_success'] = "<b>Image \"%s\" successfully copied</b> (from category %s to %s)";
$lang['copy_error_skipped'] = "<b>Image</b> %s <b>was not coppied</b>";
$lang['copy_error_thumb'] = "<b>Error copying thumbnail</b> %s";
$lang['copy_error_media'] = "<b>Error copying media file</b> %s";
$lang['copy_error_db'] = "<b>Error updating database. Image %s was not coppied</b>";
$lang['move_success'] = "<b>Image \"%s\" successfully moved</b> (from category %s to %s)";
$lang['move_error'] = "<b>Error moving image</b> %s (from category: %s to %s)";
$lang['move_error_thumb'] = "<b>Error moving thumbnail</b> %s";
$lang['move_error_media'] = "<b>Error moving media file</b> %s";
$lang['move_error_skipped'] = "<b>Image</b> %s <b>was not moved</b>";
$lang['move_error_db'] = "<b>Error updating database. Image %s was not moved</b>";