I've been having a go at using the new word lists to build some vocab lists, my plan was to build some generic vocab lists for the whole NT (ie >25 occurrences, >10 occurrences) and then use the Merge tools to intersect against the vocabulary from a book, so e.g., I created a list with all the vocabulary in Philippians and then merged that to produce a vocab list for Philippians for all words that occur <25 times in the whole NT, which seems to me to be a natural way to try and learn the vocab when you're studying a book...
Along the way I had a couple of issues:
When adding lemmas from a GNT, it didn't actually include the lemmas, and therefore lists multiple forms of the same lemma. Here's the result of adding Mark 1:1-3 from UBS4:

I had more success adding lemmas from the NIV, and created lists with all the vocab of the NT, and greater than and less than 25 occurrences. However some odd things turn up on the word counts:
Τιμὀθεος has 24 occurrences on the whole NT list, but 26 occurrences in the merged list:


In other words, it seems that the word count is just being added together when the lists are "merged". Here in this screenshot, those counts are the number of occurrences in the NT, plus the number of occurrences in Philippians. I would have thought that the Merge operations should also apply to the Counts, so that some occurrences aren't being double counted...
Or am I just trying to do things that are way off what this feature is intended for? [:)]