"Additional media is required. Please insert the %s labeled '%s' and click continue"
There is a period missing at the end.
"There was a (possibly temporary) problem connecting to a software source\n"
"Please check the detailed error for further details."
There is a period missing at the end of first sentence.
Also please check missing periods in strings in form:
I think I've fixed up all the issues in:
Author: Richard Hughes <email@example.com>
Date: Mon Jul 13 12:08:18 2009 +0100
Fix up few translations to include trailing full stop. Fixes fd#22745
Thanks for reporting this bug, and be sure to re-open this if you find any more strings that are not great. Thanks.