So I just discovered this tool. I have thousands of cards and I'm wondering if there's a fast way to enter them all rather than putting a whole bunch of 1s into 400 pages. For example, if I have an entire set is there some way for me to just click "Add entire 4th edition" for example?
In your Inventory you can click the middle tab on the add box, to get to here:

Copy/Paste in the list of cards from that set and click add. Right now that is very basic though and it will just add the card, not any details about it (like the fact that it is from 4th edition). The upcoming release should provide tools to make that type of mass adding even easier. More details on that right here.