Hello Horacio: can't help you with your concentrator but can give you a small pointer on introductions in English:
Good morning, how are you?
Good afternoon, nice to see you again.
Good evening, pleased you could come to dinner.
In your case, good evening - can you help please...
Good night, is usually used later in evening when you or someone is leaving -
You can say good bye or good night, I will see you tomorrow.
But don't worry, your post was polite and clearly understood and that is the main thing with communication, and certainly way ahead of my Spanish that consists of maybe 6 or so words

.
It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)