I can´t remeber in which version the seven get out of the MOD.
Take a look at your ingame map, you can find your MOD Version on the upper right side.
If you have the version 7.67, the update is very easy. Only download the 768upd.zip from the download section and unzip this file into your Diablo2 folder. In this case you won´t loose any items.
If you have a version prior to 7.67, you have to deactivate and deinstall your actual version. After this you can install the 7.67.exe from the download section, activate this MOD version and then follow the update description from above.
Depending on your actual version it is possible that you have to throw away all your teddys, eventually the doll-stashes and if you have any of them the morph-amuletts which has transformed the player in some of the unique Bossmonsters from Diablo2 in earlier versions. If you don´t throw away these items (depending on your version) you can´t play your old chars caused by "unknown item in inventory" errors.