[yarcob]

Oops, you are right, now that I think about it it would be weird to see a button labelled "öffne" instead of "öffnen".

I just thought that it was unlikely that the verb/adjective confusion comes from German->Italian translation, it's more likely from English->Italian.

It's a common mistake that I've already seen in software translated from English to German as well, it's just what happens when you translate English strings without context.