this is odd, I just installed 8.1 over the 8.0 and all my emoticons, extra winks and backgrounds are all there in 8.1
And I think I know why I didn't lost my smilies, is a pretty useful trick, when you use MSN Backup to save your emoticons, winks, display picture, etc. the program saves all this in files with .MCO extension, yes, that's right the extension of the MSN winks.
when you restore this backup you will notice that none of your contacts can't add your smilies to their msn, since it appear like if you bought them and were installed like you install the winks, so I think WLM 8.1 tought that my smilies were bought or something and didn't deleted them.