I downloaded the emoticons.. and, when you "get info" on them, it shows that their kind is "Folder."
This is likely the issue here. It's because they're not actually a picture file, they're a folder.. so, when you copy it to mail.. it shows up as a folder rather than the actual emoticon.
Mail is drag and drop for attachments, find the file and just drag it onto the message you're composing.
Also, it all depends on what your recipient uses to read mail. If you send an emoticon to someone who uses a hotmail account, it will prompt them to view the picture before it actually shows it to them for example. If your recipient uses Apple Mail, it will show right away.
This is likely the issue here. It's because they're not actually a picture file, they're a folder.. so, when you copy it to mail.. it shows up as a folder rather than the actual emoticon.
Mail is drag and drop for attachments, find the file and just drag it onto the message you're composing.
Also, it all depends on what your recipient uses to read mail. If you send an emoticon to someone who uses a hotmail account, it will prompt them to view the picture before it actually shows it to them for example. If your recipient uses Apple Mail, it will show right away.