As Chuck said, check out the change-log and Docs.
The documentation will be getting an update soon, but most the information should stay the same. Just click on the Game drop down menu, click on docs, click on items, and click on cube recipes and check it out. Also, I wouldn't be too afraid of hopping into the game as is, and getting a feel for how it plays. The launcher should set everything up correctly for you if you follow the instructions. If you installed Diablo 2 to your program files, some people have had issues with that, I'd move it to a folder on the desktop or else-where. Here's the link to the launcher, be warned, it's still in Beta there may be bugs. Make sure you have everything set to compatibility mode for windows XP and always run everything as admin.
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