Hi Rob,

The problem you were running into with "non-spaced-repetition" flashcards not giving you any words by default was an error in our backend. I've fixed that so it should work better now. That said, here are the basic rules for how the system decides what content to load by default:

(1) If "spaced repetition" is enabled, you'll be run through the words the system believes you need to study, and then prompted to add more vocabulary once you're finished. If you have no more words to study, you'll be given a random assortment of vocabulary (30 words) from your list and tested on those.

(2) if "spaced repetition" is disabled, you'll be given a random assortment of vocabulary (30 words) from your list.

(3) To specify a specific set of vocabulary to use, go to your vocabulary list (http://popupchinese.com/vocabulary) and label a subset of your vocabulary. View that label and then click on the Flashcards button and you'll be tested on that vocabulary.

(4) In all cases we only load 30 words each time the page loads. We do this to make sure that people don't get swamped in any particular session, and to prevent the system from freezing up if a user has literally thousands of words. Thirty seemed like a good tradeoff.

We're working on the next version of the site now, and are interested in hearing suggestions for specific improvements.