Problem importing with codification

Try to delete these two lines from your wp-config.php file:

define('DB_CHARSET', 'utf8');
define('DB_COLLATE', '');

1.-On the old WordPress, I’ve set on the admin codification to UTF-8, but on the general view on the Php Admin it says “latin1-swedish”. All was ok.

You are mixing two different things!
encoding is – utf-8
collation is – latin1-swedish

2. I looked at your feed and it seems to be OK. Show an example where it is not OK!

Actually, that Andr??s appears only on a non-existent, empty posts made on Nov 2. Nowhere else, at least in my Google Reader.