Maybe I'm too picky, but I was testing various aspects of my new installation and came across this problem. If a customer registers, I elected to have the "Join our mailing list" checkbox there. If the customer unchecks that box, the message on the next page would say they have been added to the mailing list. I would think the customer would be confused, at least I was.
Here's what I did to fix it. Added new line to shop$language_english.asp and to the language in admin. Make sure to reload the the shop configuration after you add it.
LangRegistered="You have registered as a customer."
In shopcustregister.asp in the WriteInfo subroutine around line 90, make the IF statement look like this:
If getsess("customeradmin")="" then
if blnMailList = "False" then
Now the customer will receive the proper message if they joined the mailing list or not.