Just to inform you about the problem you may have when generating again languages.
I installed 5.5.4 and I saw it overrided my personal italian translation, so I checked for italian presence in latest lang.xml, and I saw the italian column (it) is not aligned with the index (Lis), so, starting from row 15, italian translation is in no way associated with the real meaning.
Regards.
I found no issue on lated lang.xls...
I sotred latest version (V6.1) on download page.
Can you check it is correct ?
Now it is correct, at a quick look.
Version I've found before had the last version row tagged as 6.0.0.